The Seeds of Doom (TV story)

The Seeds of Doom was the sixth and final story of Season 13 of Doctor Who. It marked the Doctor's final major involvement with UNIT until Battlefield in Season 26. It is also the first televised UNIT story in which neither the Brigadier nor Benton appears, with the Brigadier unable to help as he was 'in Geneva'.

It was originally intended for The Hand of Fear to be the finale, but the scripts were not ready in time, so The Seeds of Doom filled the gap.

Colour Separation Overlay, or CSO effects, were to be used in The Hand of Fear. These were best achieved with Outside Broadcast (OB) videotape. After The Hand of Fear's cancellation, The Seeds of Doom inherited the booking for OB tape. This allowed the story to feature an unusually large creature.

Synopsis
When scientists in the Antarctic uncover two mysterious seed pods, the Doctor is called in to investigate. He soon realises they are extraterrestrial and extremely dangerous. At the same time, however, ruthless plant-lover Harrison Chase has learned of the find and decides he must have the pods for his collection of rare and beautiful flora. And the pods themselves harbour intelligent life with sinister plans of its own...

Part one
Somewhere in Antarctica, scientists Charles Winlett and Derek Moberley discover an egg-shaped object in the ninth layer of the permafrost, and take it back to their camp. John Stevenson, the base botanist, identifies it as vegetable-based and estimates it has been buried in the ice for some 20,000 years. Winlett thinks it looks tropical, like a gourd, but Moberly points out that Antarctica had ceased to be tropical at the time this was buried. Stevenson claims he feels something odd about the pod, as if it is alive, but the others laugh it off. Back in London, Richard Dunbar of the World Ecology Bureau tries to show the Doctor photographs of the pod. Although he feels that the Doctor cannot help them, his superior Sir Colin Thackeray insisted. The Doctor examines the pictures and asks if they had considered the idea that the pod is extraterrestrial. He tells Dunbar to contact the expedition by their regular video link, and tell them not to touch it until he arrives.

Back at the base, Stevenson discovers that the pod is growing larger and he believes it is absorbing ultraviolet radiation. Winlett reminds Stevenson that London's orders are to leave it alone until the Doctor arrives tomorrow, but Stevenson thinks the Doctor is just some crank Thackeray is foisting on them. He feels it is their discovery and they can do what they want with it.

In England, Dunbar visits the estate of millionaire Harrison Chase. Chase's estate is filled with thousands of plants, and he considers it his mission to protect the plant life of Mother Earth. Dunbar has come to show him pictures of the pod and its possible extraterrestrial origin, and hints that such a valuable specimen could easily disappear... for a price.

Chase wants to know the precise location it was found, and Dunbar gives it to him. Chase calls for one of his men, Scorby, and gives him an assignment, telling him to take Keeler along.

At the base, Winlett is half asleep near the pod. The pod opens up and a frond-like tentacle whips out and stings his arm, causing Winlett to collapse in pain. When Stevenson and Moberly find him, Winlett's face is covered with green hives. A message is sent to London informing them of the situation, but with the bad weather, it will take a few days for a medical team to reach the base.

Meanwhile, the Doctor and Sarah Jane Smith arrive at the base by helicopter and are met by Moberly. He tells them that usually up to a dozen live at the base but currently the others are 60 miles away at South Bend, measuring the ice cap.

In the sickbay, Winlett's body temperature is dropping rapidly, as is his pulse rate. His face and body are now covered with a green fungus, and its growth is accelerating. By the time the medical team arrives it may be too late. However, Mike Wilson from South Bend radios them that the medical team has turned back due to whiteout conditions.

The Doctor asks for a blood test on Winlett and examines the now-empty pod. Stevenson acknowledges that it may be his fault; convinced that the pod was alive he placed it under a lamp. The Doctor tells him that his actions could result in the destruction of all life on the planet.

Moberley draws a sample of blood from Winlett, who is growing increasingly monstrous. Outside the base, the Doctor digs at the ice, uncovering another pod. Stevenson asks if there are any more and the Doctor shakes his head: the pods travel in pairs, "like policemen." He transfers the pod to the base freezer. On analysis, Winlett's blood is found to contain no blood platelets, but instead has schizophytes — microscopic organisms akin to plant bacteria.

The sound of engines is heard, and Moberley and Stevenson go meet what they presume is the medical team. The Doctor tells Sarah that Winlett is turning into a Krynoid, a kind of galactic weed that settles on planets and eats the animal life. He does not know exactly how the Krynoids travel between the stars — their planet may be geologically turbulent, with surface explosions sending matter shooting into space.

Stevenson and Moberley escort two men — Scorby and Keeler — into the base. The new arrivals were flying a private plane, but claim they got lost and wound up at the base. The Doctor leaves to check on Winlett, taking the others and leaving Scorby and Keeler alone.

Winlett's transformation is nearly complete. The Doctor suggests that the arm be amputated to try to stop the spread of the infection at its source. Even if it does not work, it might buy them time. As the Doctor is not a doctor of medicine and Stevenson is a botanist, Moberly is the most qualified. Moberley is hesitant but Sarah persuades him in the end. As they leave to gather the necessary equipment, Winlett rises from the bed.

When Moberley starts back towards the sickbay, he spots Winlett leaning against the wall. As Moberly approaches, Winlett reaches out and strangles him...

Part two
Winlett leaves Moberly's dead body in the corridor and leaves the base. Meanwhile, Scorby finds the base's rifle and unloads it. Keeler is nervous, thinking that all they are here to do is to confirm the existence of the pod and report back to Chase, but Scorby disabuses him of the notion: they are to kill the others, take the pod and fly back. If Keeler is squeamish, Scorby warns him, there will be one more among the dead.

Sarah finds Moberly's body. Stevenson cannot believe that Winlett has done this, but the Doctor tells him that Winlett no longer exists; his mind has been taken over and soon he will turn completely into a Krynoid. They gather their things to search for the creature and take the rifle, not realising it has been sabotaged. When the others leave, Scorby and Keeler go in search of the pod.

Dunbar tells Chase about a report of an infection at the base, but is shocked when Chase tells him he has sent his own men to Antarctica. Dunbar seeks an assurance that should anything go wrong, Chase will protect his identity. Chase pays Dunbar off.

The Krynoid finds the generator hut — built far from the base because of its new fuel cell system. However, when it sees the Doctor, Stevenson and Sarah approach, it turns away. Unable to find the Krynoid, and hoping that it is frozen in the snow, the three head back to base, and the Krynoid seeks shelter in the hut after their departure.

Meanwhile, Scorby and Keller ransack the base. When South Bend calls to say the weather has cleared and the medical team are now on their way, Scorby pretends to be Moberly and tells them help is no longer needed. When South Bend gets suspicious, Scorby disconnects the radio. Keller finds the open pod, and realises that it has germinated. Scorby wants to find the actual plant that emerged, but they find Moberly's body in the sickbay instead.

When Sarah and the Doctor enter the sickbay, Scorby holds them at gunpoint. Scorby questions the Doctor about Moberly, and the Doctor tells them about the pod and Winlett's infection. When Stevenson discovers them, he finds his rifle useless and is put with the others, but lets slip that a second pod exists.

Scorby wants the second pod. He threatens Sarah's life and the Doctor relents, telling Scorby the second pod is in the freezer. Stevenson is forced to take it out and places it in a thermal container to keep it cool and safe. After this is done, Scorby forces Sarah to take him to the generator hut with Keeler in tow, leaving the others tied up behind. While the Doctor knocks over an unlighted kerosene lamp and uses the broken glass to cut Stevenson's bonds, Scorby plants a bomb in the hut which will blow up the base. Keeler gets cold feet and tries to stop Scorby, who tosses him out of the hut.

Freed, the Doctor tells Stevenson to contact South Bend for the medical team, and goes in search of Sarah. However, the Krynoid has returned to the base, and kills Stevenson while he is making the call. The Doctor sees Scorby and Keller's plane take off, and runs to the generator hut where Sarah is tied up. She tells him about the bomb, but the creature arrives as well. They get out the door and lock the Krynoid in; they run away as the hut explodes, taking the rest of the base with it...

Part three
Regaining consciousness in the snow, the Doctor and Sarah are picked up by a team from South Bend in their Snow Cat vehicle. Meanwhile, Scorby and Keeler return to Chase with the second pod. Dunbar also arrives, angered at how far Chase had gone to secure the pod, but warns Chase that the Doctor and Sarah are still alive, and are scheduled to meet with him and Sir Colin in two hours.

At the meeting, the Doctor and Sarah describe how well-planned the theft of the pod was, but the Doctor believes that the two men were stooges. The discovery of the pod had only been reported to the Ecology Bureau, so the leak must have come from them. The Doctor is sure that the pod is in England, and says that if they do not find it, it will be the end of everything — even Sir Colin's pension. He tells Dunbar to arrange for him to go to the Botanic Institute.

As they leave the building, a driver comes up and claims to be their car, and the Doctor and Sarah board the limousine. The car stops in the countryside, and the driver orders them out at gunpoint. As they exit, the Doctor knocks the driver over and both he and Sarah run for it. With a bit of teamwork, the Doctor jumps the driver and punches him out. The two search the car, and find a painting by Amelia Ducat, one of the world's leading flower artists, in the boot. When they go and speak to her, she tells them that the owner of the painting is Harrison Chase, and that he never paid her for the painting.

Keeler, who is a botanist himself, unsuccessfully tries to convince Chase to stop the experiments on the pod. Chase orders him to inject the pod with fixed nitrogen. Dunbar calls Chase and tells him that his chauffeur is in hospital. So when the Doctor and Sarah try to sneak into the mansion, they are spotted by some guards and Scorby, who capture them.

The Doctor and Sarah are brought before Chase and despite having Scorby's gun at his head, the Doctor asks Chase grimly to hand over the pod. Chase politely refuses: he has the greatest collection of plants in the world, and when the pod flowers, it will be his crowning achievement. Before he executes them, Chase decides to show the Doctor and Sarah around the mansion and his plant laboratory.

Keeler notes that the pod is growing, and tells Hargreaves, the butler, to summon Chase to the annex. There, Chase tells Keeler to inject more nitrogen into the pod. Scorby escorts the Doctor and Sarah into the gardens to kill them, but the two overpower Scorby. The Doctor uses rope to lower Sarah down the wall so she can go and warn Sir Colin, while he returns to the house to examine the pod. However, Sarah gets captured again.

The Doctor makes his way back into the mansion while Sarah is escorted by Scorby back to Chase. The Doctor watches, horrified, through the skylight as Chase orders Sarah forced down to a chair, grabbing her arm and pinning it next to the pod. He wants to know what happens when the Krynoid touches human flesh. As Sarah struggles, the pod begins to open...

Part four
The Doctor crashes through the skylight, knocking Scorby out and grabbing Sarah. They rush out the door, locking Chase and his men in. As Chase tries to get the guards' attention, a frond from the pod stings Keeler's arm. Finally, a guard opens the door; he and Scorby go in pursuit of the Doctor. Sneaking around the grounds again, the Doctor tells Sarah once more he is returning to examine the pod.

Keeler begs Chase to get him to a hospital, but Chase is more fascinated with the transformation process than saving Keeler's life. Chase and Hargreaves take Keeler to the nearby cottage. Chase observes that the growth seems to be absorbing protein from Keeler's body, and tells Hargreaves to keep Keeler fed.

When the Doctor returns to the laboratory he finds it empty, but Scorby now has the drop on him. Scorby and the guard take the Doctor to the compost room. Scorby activates the crusher, remarking that Chase recycles everything. The main gate calls the house: Amelia Ducat is here demanding her money. To avoid a fuss, Chase agrees to see her. Sarah has entered the cottage, and sees Keeler, who is still lucid, although covered with the Krynoid growth. Keeler tries to convince Sarah to free his bonds, and when Sarah refuses, he grows more angry and paranoid. Sarah hides in a cupboard when she hears Hargreaves approach with a meal and leaves at the first opportunity.

In the library, Chase writes Ducat a check. Scorby enters and asks if they should start the "recycling experiment", and Chase says he wants to see it, asking Scorby to escort Ducat out. Chase goes to the compost room, and reveals that he has been feeding Keeler. The Doctor, tied up, is placed in the machine, to be shredded and pumped into the garden.

Sarah is back in the house, and hides behind a suit of armour as Ducat and Scorby pass. Sarah attracts Ducat's attention and asks her to take a message to Sir Colin. Sarah goes back into hiding when Scorby returns to show Ducat out. Outside, Ducat enters a car with Sir Colin and Dunbar inside, and tells them what Sarah said. Dunbar, realising he has made a terrible mistake, says he will go in and get the Doctor. He tells Sir Colin that, if he does not return in half an hour, he must return to London and call UNIT. Sarah finds her way into the compost room and turns off the crusher just in time to save the Doctor. Hargreaves finds that Keeler has now almost completed his transformation, and runs in a panic as the creature frees itself. In the mansion, Dunbar pleads with Chase to abandon the experiment as Hargreaves reports Keeler's transformation to Chase. Dunbar says that this has gone far enough, and he is going to get help. Chase tells Scorby to stop him.

Scorby pursues Dunbar through the grounds as the Doctor and Sarah find Keeler missing from the cottage. The Doctor takes a sword from over the fireplace and they leave to search for it. Dunbar runs into the Krynoid, which is far larger than the Winlett creature was, and no longer even humanoid. He shoots at it uselessly, and is held fast by the surrounding plant life as the Krynoid kills him. Dunbar's screams attract the attention of Scorby and the guards as well as the Doctor and Sarah. The latter get there first, the Doctor drawing the sword above Dunbar's body as the Krynoid lurches towards them...

Part five
The Doctor and Sarah Jane arrive just as the Krynoid finishes off Dunbar. The creature advances on them but Scorby and his men show up and distract it with otherwise useless gunfire. They all escape to a cottage and barricade themselves in. Scorby is shocked that the creature was once Keeler. Chase calls them and orders Scorby to capture rather than kill the Krynoid and cuts off before the Doctor can explain.

The Krynoid smashes a window and extends a tentacle inside but they manage to drive it off. The Krynoid speaks using Keeler’s voice, demanding that the Doctor come out and join it and it will spare the others. Scorby is more than willing to give up the Doctor until Sarah Jane points out that without the Doctor they have no chance. The Doctor suggest Scorby rig up a bomb so they can all escape while the Krynoid is distracted.

Sir Colin tries to get through on the phone while Amelia gives him some advice. Sir Colin tries to contact the Brigadier and UNIT but Lethbridge-Stewart is out of the country. He eventually gets through to Major Beresford for assistance and sends Amelia home.

Chase prepares to take photographs of the Krynoid, claiming he has nothing to fear from it. The Doctor and Scorby initiate their plan as Chase arrives outside. Scorby throws his improvised bomb out an upstairs window and the Doctor makes a run for it. The Krynoid goes in pursuit, but the Doctor escapes in the limousine, leaving the Krynoid behind. Scorby tries to find Chase at the greenhouse and discovers where he is from Hargreaves. They begin barricading the windows in preparation for the Krynoid’s attack. Chase makes his way through the grounds and confronts the Krynoid. It notices him and he approaches, taking photographs. It moves toward him as Chase claims he doesn’t mean it harm.

The Doctor arrives at the Bureau as Major Beresford warns he can’t do anything without evidence. The Doctor warns the Krynoid can channel its power through other plants, turning vegetation against humans. He shows them a series of reports of deaths of people near Chase’s estates being killed by plants. He then calls Sarah Jane and tells them Beresford is preparing to attack the Krynoid with a laser gun, but the Krynoid cuts the phone wires.

Chase wakes up in the woods and has clearly had a major experience: He begins talking about how the world will be recreated.

Scorby arrives and Sarah Jane points out how the vegetation around the windows is getting thicker. When Hargreaves reports that he heard screams, Sarah Jane taunts Scorby into going to investigate with her, and they find a dead guard killed by plants. Chase arrives and tells them that it’s the plants’ world, and humans are only parasites. He goes to the manor to develop his photographs, then begins speaking to the plants in his greenhouse.

Scorby, Sarah Jane, and Hargreaves go in to confront Chase and he speaks of how the world will be made perfect. They can’t get through to him as he talks about how he is one with the plants and animals are the enemy. Sarah Jane notices that the plants are closing in on them. The Doctor and a UNIT soldier drive onto the grounds while the plants overwhelm Sarah Jane and the others and start to strangle them. The Doctor and the UNIT soldier, Sgt. Henderson, arrive and bring chemical plant-killer. They dispose of the plants, saving Scorby and Sarah Jane while the older Hargreaves is dead. Chase runs away and the Doctor and the others make their way into the lab and start removing the plants. But once they're outside Chase locks the door behind them and they can only gaze in horror as the now enormous Krynoid towers over them....

Part six
UNIT soldiers arrive and open fire with their laser gun, distracting the Krynoid so that the Doctor and his group can get to another door. The Doctor believes that Chase is possessed by the Krynoid and determines to find him and eliminate the threat he poses to them from within. After they leave, Chase slips back into the laboratory and destroys the loudspeaker system. Unable to find the millionaire, the others return to the laboratory and the Krynoid tries to break its way in. Henderson goes to get more timber to barricade the windows and Chase knocks him out.

Scorby starts to panic and wants to run, but the Doctor warns him that every plant on the grounds is under the Krynoid’s control. Meanwhile, Chase puts Henderson in the compost machine and activates it, killing the unconscious soldier.

The Doctor works to repair the loudspeaker system as the Krynoid renews its attack, and Scorby panics and runs for it. He tries to make his way across the grounds through fields of hostile plants and makes his way across a shallow pond, but the plants grab and pull him underwater, killing him.

The Doctor and Sarah Jane realise that Henderson is gone and Sarah Jane goes to look for the soldier. She makes her way to the compost machine room and Chase confronts her, telling him he’s become part of the plant world thanks to the Krynoid. Chase plans to support the Krynoid and refers to humanity as parasites, then attacks Sarah Jane.

Beresford contacts the Doctor, who warns they have 15 minutes until the Krynoid germinates, spreading its seeds across England. The Doctor tells them to launch an air strike before it’s too late, and regardless of the fact he and Sarah Jane are at ground zero.

Chase has tied up the unconscious Sarah Jane and starts feeding her into the compost machine. The Doctor arrives, sends Chase flying, and shuts off the machine to untie Sarah Jane. He gets her out but Chase turns the machine back on and throws himself at the Doctor, and the two struggle inside the machine's bin. The Doctor climbs out as Chase is pulled into the machine despite the Doctor’s efforts to save him.

The RAF launches a sighting run as Beresford and Sir Colin look for any signs of the Doctor. Sarah Jane and the Doctor can’t get out through the plant life covering the house but the Doctor rigs a steam pipe and they blast their way out. They make their way through the hostile plant life and take refuge in a clearing filled with cut-down trees, as the RAF opens fire and destroys the Krynoid.

Later, the Doctor, Sarah Jane, and Sir Colin discuss the apparent destruction of the Krynoid. Sir Colin wants the Doctor to address the Royal Horticultural Society but the Doctor instead offers to take Sarah Jane on a vacation to Cassiopeia. However, the TARDIS materialises in Antarctica when the Doctor forgets to reset the coordinates. Simultaneously, the Doctor and Sarah Jane say, "Have we been here before or are we yet to come?"

Cast

 * The Doctor - Tom Baker
 * Sarah Jane Smith - Elisabeth Sladen
 * Scorby - John Challis
 * Harrison Chase - Tony Beckley
 * Richard Dunbar - Kenneth Gilbert
 * Sir Colin Thackeray - Michael Barrington
 * Amelia Ducat - Sylvia Coleridge
 * Arnold Keeler / Krynoid Voice - Mark Jones
 * Hargreaves - Seymour Green
 * Derek Moberley - Michael McStay
 * John Stevenson - Hubert Rees
 * Charles Winlett - John Gleeson
 * Doctor Chester - Ian Fairbairn
 * Major Beresford - John Acheson
 * Sergeant Henderson - Ray Barron
 * Chauffeur - Alan Chuntz
 * Guard Leader - David Masterman
 * Guard - Harry Fielder

Crew

 * Film Editor - M A C Adams
 * Designer - Jeremy Bear
 * Make-Up - Ann Briggs
 * Incidental Music - Geoffrey Burgon
 * Director - Douglas Camfield
 * Visual Effects - Richard Conway
 * Studio Lighting - John Dixon
 * Production Unit Manager - George Gallaccio
 * Title Music - Ron Grainer and the BBC Radiophonic Workshop, arranged by Delia Derbyshire
 * Production Assistant - Graeme Harper
 * Producer - Philip Hinchcliffe
 * Script Editor - Robert Holmes
 * Studio Sound - John Holmes
 * Film Cameraman - Keith Hopper
 * Costumes - Barbara Lane
 * Special Sounds - Dick Mills
 * Designer - Roger Murray-Leach
 * Production Unit Manager - Janet Radenkovic
 * Assistant Floor Manager - Sue Shearman
 * Writer - Robert Banks Stewart
 * Fight Arranger - Terry Walsh

Organisations

 * The Doctor is called in as an expert by Sir Colin Thackery of the World Ecology Bureau.
 * The Doctor states that he is President of the Intergalactic Floral Society.

Planets

 * The Doctor tries to take Sarah to the planet Cassiopeia.

Species

 * The Krynoid, a 'galactic weed', has been buried for at least 20,000 years.

Handheld weapons

 * Molotov cocktail
 * Sword
 * FN FAL Rifle
 * Uzi sub-machine gun

Foods and beverages from the real world

 * A pilot declared he was going to turn the Krynoid into Chop suey.

Story notes

 * An early version of The Hand of Fear was originally scheduled to be produced as the final serial of Season 13. However, there were serious problems with the scripts, so script editor Robert Holmes and producer Philip Hinchcliffe commissioned a new script from writer Robert Banks Stewart, at very little notice. The Hand of Fear was substantially reworked and produced in the following season.
 * In this period, location filming for Doctor Who was usually done on 16mm film. However, exteriors for this story were filmed on video using outside broadcasting, which had previously been used in Robot and The Sontaran Experiment.
 * Episodes 1 and 2 are heavily influenced by Howard Hawks' 1951 film The Thing From Another World: an artefact found frozen in the Antarctic ice is revealed to be a deadly plant-like alien. The film was itself based on the short story, Who Goes There?, written by John W. Campbell, Jr. Others have noticed a strong similarity between this story and Man-Eater of Surrey Green, an instalment of The Avengers television series of the 1960s, and also the 1953 BBC production The Quatermass Experiment. On the DVD commentary for The Seeds of Doom, Robert Banks Stewart says that he has been accused of stealing the notion of a hostile and mobile alien plant from , but states that the stories merely draw from common roots.
 * This serial was the last serial to use the Brachacki police box prop.
 * The serial also marked the final major appearance of UNIT in the series until 1989's Battlefield (although it would be referenced in the Fifth Doctor story Time-Flight, Brigadier Alistair Gordon Lethbridge-Stewart appeared in the 1983 story Mawdryn Undead as a retired civilian, and there is a sequence set at UNIT HQ in The Five Doctors). None of the established UNIT characters are seen in UNIT's brief appearance in this story, as it was felt that there was too little material to warrant bringing back the Brigadier and Sergeant John Benton. Although the Doctor worked with UNIT in later stories (continuing into the mid-2000s revival), this is the last story to date in which the Doctor is explicitly shown to be working for UNIT.
 * The story was director Douglas Camfield's last involvement with Doctor Who. Camfield went on to direct other television programs and died in his sleep in 1984.
 * A few weeks before the serial was due to begin its original transmission, the master tape for the first episode was found to be missing. A brief panic ensued and producer Philip Hinchcliffe began planning a re-edit of the second episode allowing the story to begin at this point, but fortunately the tape of the opening episode was eventually located, having been misplaced in the tape storage system (apparently due to having been wrongly numbered).
 * The costume for the humanoid stage of the Krynoid was created by taking one of the surviving Axon costumes from The Claws of Axos and spraying it green.
 * The name 'Krynoid' would appear to be adapted from '', a small flower-like creature, related to star fish and sea urchins, that live in shallow and deep oceans worldwide.

Ratings

 * Part 1 - 11.6 million viewers
 * Part 2 - 11.4 million viewers
 * Part 3 - 10.3 million viewers
 * Part 4 - 11.1 million viewers
 * Part 5 - 9.9 million viewers
 * Part 6 - 11.5 million viewers

Myths

 * This story was originally written as a four-parter and the opening two episodes were added by script editor Robert Holmes and/or director Douglas Camfield. (It was commissioned and written as a six-parter by Robert Banks Stewart from the outset.)
 * The location scenes for this story were shot at a house owned by rock star Mick Jagger. (Jagger's house, Stargroves near Newbury in Hampshire, was used as a location for Pyramids of Mars; the house seen in The Seeds of Doom is Athelhampton House in Athelhampton, Dorset.)

Filming locations

 * Athelhampton House, Athelhampton, Dorset (Chase's Estate exterior)
 * Buckland Sand and Silica Co Ltd, Reigate Road, Buckland, Surrey
 * BBC Television Centre (Entrance), Shepherd's Bush, London (World Ecology Bureau entrance)
 * BBC Television Centre (TC4, TC8), Shepherd's Bush, London

Production errors
to be added

Continuity

 * The Doctor also encounters the Krynoids in ST: Stop the Pigeon and BFA: Hothouse.
 * Krynoids also appear in BBV: The Root of All Evil and The Green Man.
 * A Krynoid also makes a cameo appearance in BBV: Do You Have a Licence to Save this Planet?
 * This is the last full appearance of UNIT for thirteen years, until DW: Battlefield in 1989.
 * The Doctor previously visited Antarctica in December 1986 towards the end of his first incarnation. (DW: The Tenth Planet)
 * Sarah Jane would later return to Antarctica in 2006. (BFSJS: Snow Blind)

Timeline

 * This story takes place after TVC: Double Trouble.
 * This story takes place before DWAN: The Sleeping Beast.

Video releases
This story was released in the UK on VHS video in 1994, Australia later in 1994 and the US in 1995.

DVD releases
This story was released on DVD 25th October 2010. The two disc release contains the following extras:


 * Pod Shock (making of)
 * Playing in the Green Cathedral (featurette on composer Geoffrey Burgon)
 * So What Do You Do Exactly? (featurette on the roles of production assistant and Production unit manager)
 * Now & Then - The Locations of The Seeds of Doom
 * Photo Gallery
 * TV Continuity Announcements
 * Stripped for Action - The Fourth Doctor
 * Radio Times Listings
 * Douglas Camfield's Paper Edit
 * Easter Egg: Outtake. To access this hidden feature, press right at 'Playing in the Green Cathedral' on the bonus disc.
 * Easter Egg: John Challis (Scorby) shares a personal anecdote about his relationship with Tom Baker. To access this hidden feature, press left at 'Photo Gallery' on the bonus disc.
 * Coming Soon Trailer for DVD release of Meglos

CD release
In 2000 a CD was released with Terror of the Zygons.