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The Underwater Menace was the fifth serial of season 4 of Doctor Who.

As of 2022, its second episode is the earliest surviving Second Doctor telerecording known to exist. Currently, only episodes two and three survive in full.


The TARDIS arrives on an extinct volcanic island. Before long, the travellers are captured and taken into the depths of the Earth, where they find a hidden civilisation — the lost city of Atlantis.

The Atlanteans worship a goddess named Amdo and use fish people — men and women operated upon so that they can breathe under the sea — to farm the plankton-based food on which they survive. A deranged scientist, Professor Zaroff, has convinced them that he can raise their city from the sea, but actually, he plans to drain the ocean into the Earth's molten core so that the resultant superheated steam will cause the planet to explode.

The travellers meet up with two shipwreck survivors, Sean and Jacko, who persuade the fish people to rebel and stop work. The Doctor eventually foils Zaroff's plan, but only by breaking down the sea walls and flooding the city. Zaroff drowns, but everyone else escapes.


Episode 1[]

Jamie is blown away by the interior and the workings of the TARDIS. The Doctor quotes Robert Burns to him — which confuses him further due to the fact that Burns wouldn't be born until ten years after Jamie left in the TARDIS. The TARDIS materialises on a volcanic island.

The crew explore their surroundings; Ben, Polly and Jamie climb up a shallow hill for a better vantage whilst the Doctor begins to investigate the rocks to give him a clue as to their whereabouts.

As the three companions climb, Polly thinks she sees something in the distance, but Ben and Jamie say she must be imagining it. Polly decides to wait for the boys as she is running out of breath. They leave her on a ledge to return for her when they reach the top. She begins to explore and finds a bracelet that she examines very closely before beginning to explore a nearby cave. Here she is confronted by robed figures. She screams, which alerts Jamie and Ben. They return back to the cave and begin to explore. They are ambushed by the robed figures, who then capture them and put them in a small room where Polly is tied up. They discuss what to do until the door opens again and the Doctor is thrown in with them. Once all four are together, the room begins to descend like an elevator. The companions suffer difficulty in breathing, nausea and a strange taste in their mouths before they fall unconscious.

They awake later in a compression chamber. The Doctor wonders what time period they are in and Polly takes a stab at the 1970s. When challenged, she reveals the bracelet which is a souvenir from the 1968 Olympics in Mexico, alluding to the fact that it must be some point after that. A guard armed with a spear enters and Polly and Jamie try to communicate with him but to no avail. He gesticulates with his spear, indicating that they should go down a corridor.

They are taken to a dining hall and given a dinner of plankton. The armed guard is hostile towards a serving girl called Ara, whom the Doctor sticks up for. Lolem, a priest, arrives and says that their goddess Amdo prophesied visitors falling from the sky before one of their festivals. He orders his guards to seize the four travellers in preparation for their sacrifice. As they are dragged away, the Doctor says he has something important he needs to say. Lolem humours him and says he has five minutes whilst his friends are dragged away. The Doctor says that Professor Zaroff, who he has deduced to be there, would be very disappointed if he heard that Lolem had killed him. When questioned as to how he knew Zaroff was there, the Doctor states that only he could produce such delicious food from plankton. Lolem says that this changes nothing and that the Doctor will still die. The Doctor asks for him to send a note to Zaroff. Lolem forbids this, but the Doctor smuggles the note to Ara and asks her to deliver it.

The companions have been led into a temple surrounded by a moat of shark-infested water. Ben, Polly and Jamie are tied up and placed on ramps that tilt into the water. The Doctor is led into the temple, tied up and placed on the fourth ramp. The ramps slowly begin to lift. The four victims try to cling on as best they can.

Ara goes to Zaroff's quarters and is forbidden entry. She then asks to see someone called Damon. Damon is given the note which reads, "Vital secret will die with me. Dr W." Damon immediately gives the note to Zaroff, who rushes out and stops the ceremony and orders the Doctor to be released. Initially, his companions are to be consigned to their fate, but the Doctor tells Zaroff that he will not tell his secret whilst his friends are in danger. They are sent to the labour controller while Zaroff and the Doctor speak privately. It is revealed that Zaroff faked his own death, allowing the world to think he was assassinated or kidnapped in a plot between East and West Germany. The Doctor flatters him so much that when he admits that he has no secret, Zaroff praises him for his sense of humour and allows him to live.

Damon is in charge of the labour and sends Jamie and Ben to the mines. When left alone with Polly, he slightly intimidates her before showing her Zaroff's plans. Outside are farmers who have been given plastic gills in order to farm food under the water. Polly marvels at this but blanches when she discovers that this is the fate that Damon has in mind for her.

The Doctor and Zaroff talk and the Doctor deduces that they are in the lost city of Atlantis. Zaroff reveals that, in return for raising Atlantis, he was allowed to practice his experiments in the city. Ara comes and informs the Doctor of Damon's plans for Polly. The Doctor tells Ara to go back to Polly, watch over her and, if she has a chance, to get her away from Damon.

However, it seems too late as Polly is on the cusp of being anaesthetised by Damon.

Episode 2[]

Whilst being shown round a laboratory, the Doctor fiddles with the lighting, which affects the operating room. This stalls the procedure. Damon storms up to the laboratory, demanding to know why Zaroff is draining so much power. Zaroff shows Damon he has a separate generator. Whilst the two argue, the Doctor fuses the generator, plunging the operating room into darkness. The two doctors leave Polly to see what is going on. Ara sneaks in and frees Polly — taking her to the caves.

The Doctor in Zaroff's lab as Damon confronts Zaroff.

Damon is furious with the Doctor, and even Zaroff agrees it is best if the Doctor stays with him. Zaroff explains to the Doctor that he plans to core into the centre of the Earth and drain the water away so as to render Atlantis accessible by land. The Doctor realises it will blow the planet apart and Zaroff concedes that this is an issue, before stating that will be his final testament.

Down in the mines, Ben and Jamie meet Sean and Jacko. They are immediately ingratiated into their gang when Jamie helps them hide a compass from the dictatorial foreman. They explain that they are going to use the compass for a breakout plan.

The Doctor discovers that Polly has been freed and escapes from Zaroff's lab by creating a chemical reaction that causes a stultifying effect on those that breathe in the fumes.

Sean and Jacko explain that they have found an underground shaft which they will use to escape. Ben and Jamie will join them. An alarm sounds in the mine, which means the group is going to separate. The four decide to slip away in this process.

The Doctor has sneaked into the cave system. He encounters Ara, who tells him Polly is safe. While they talk they overhear a priest called Ramo talking to Damon. The Doctor discovers that Ramo also mistrusts Zaroff. The Doctor asks Ara to distract Damon so he can talk to Ramo privately. Ara approaches Damon and tells him that she saw Polly in the marketplace. Damon falls for it, and the Doctor approaches Ramo. He goes to call out, but the Doctor convinces him that he has important information regarding Zaroff. They go somewhere private to discuss.

The party of escapees decide to split up to find the best way through the mines. At the temple, the Doctor shows Ramo what Zaroff intends to do using a jug and a fire as props. Ramo is convinced and says he will summon him to an audience with the supreme leader Thous but warns the Doctor that Thous is a strong advocate of Zaroff's and it won't be easy to convince him.

The Doctor and Ramo, confronted by Zaroff.

Jacko joins up with Sean and Ben to say that Jamie has slipped down a cliff edge. Sean goes on to see if there's a better means of escape while Jacko and Ben go back to help Jamie.

Back at the temple, Ramo gives the Doctor some ceremonial robes in order to get him close to Thous. As soon as they leave, Polly leaves from her hiding place. As she does, a secret door in the temple opens and Ben, Jamie, Sean and Jacko emerge.

Once alone, the Doctor and Ramo explain Zaroff's plan to Thous. He asks to be left alone to consider his options. Ara returns to feed the refugees but is interrupted by people entering the temple. Everyone except Ara hides in the secret compartment.

The Doctor and Ramo are summoned to the temple. Thous says he has considered both their opinions. Just then, Zaroff and his guards enter and Thous tells Zaroff to do with them what he will.

Episode 3[]

The Doctor tries to protect Ramo by telling them that he was led astray by him, but Ramo stands up for himself and states he has always hated and mistrusted Zaroff. The Doctor and Ramo are led away to be fed to the sharks. When left alone with Thous, Zaroff promises him that the Doctor's stories were untrue.

The Doctor and Ramo are brought by Lolem and the other priests to the idol of Amdo. They are about to be beheaded as a sacrifice and fed to the sharks when a voice issues from the statue of Amdo, commanding all present to bow their heads. The Doctor, recognising the voice as Polly's, escapes with Ramo and meets up with his friends in the secret enclave in the temple. On rising from their prayer and finding the Doctor and Ramo gone, Lolem claims it to be a miracle. The statue has a mouthpiece on the inside designed for people to sound like their words are emanating from the idol.

The Doctor, hiding in the Atlantis market in disguise.

Zaroff tells Thous that his plans will come to fruition in two days' time. Lolem enters and tells Zaroff and Thous of the "miracle". Zaroff is scathing of Lolem's stupidity and orders Atlantis searched despite the doubts of Thous.

Inside the idol, the Doctor makes his plans: Sean and Jacko will convince the fish people to stop supplying the perishable plankton to Atlantis, and the rest will kidnap Zaroff. The Doctor and Polly disguise themselves as regular Atlantis shoppers in the marketplace whilst Jamie and Ben disguise themselves as guards. Avoiding the real guards, the four of them trick Zaroff away from his guards and into the temple where he is captured.

Meanwhile, Sean insults the fish people until they are in such a state of disarray that they agree to stop production to get back at Zaroff, the man Sean blames for their current state of servitude.

Zaroff taunts the Doctor, saying that without him the plan will still go ahead. The Doctor doubts this, stating that Zaroff's egomaniacal ways would stand in the way of such a hands-off approach. Zaroff becomes enraged by this and falls into a fit. The Doctor takes Ben and Jamie to the laboratory to check on Zaroff's progress while Polly and Ramo guard Zaroff. A service is going on outside, so the Doctor and his companions hide until it is finished.

Inside the idol, Zaroff repents his behaviour and begs Ramo to help him up so he can pray with him. Ramo consents after convincing from Polly. This is a trick, and a scuffle breaks out between the two. Eventually, Zaroff stabs Ramo and disappears into the cave system with Polly as his hostage.

Once the service has finished, the Doctor decides Jamie should go back and ask Ramo for directions. As he turns back, he meets the mortally injured Ramo, who mutters about Polly's abduction before dying. The Doctor sends Jamie after Polly whilst he and Ben go on to the laboratory.

Jamie catches up with Polly and overpowers Zaroff. A fight breaks out between them. Zaroff appears to have the upper hand when Sean and Jacko join the fight. Zaroff runs off into the cave system. Polly decides they need Ara to help reunite them the Doctor.

Back at the council chamber, Thous is informed by Damon of the revolt of the fish people. He agrees to enter discussions with them. Zaroff enters and overrules this, saying that any dissenting fish people will be killed. Thous says he has no right to overrule him and attempts to arrest Zaroff. Zaroff shoots Thous and then orders his two guards to kill Thous' guards — which they do. He then vows that nothing in the world can stop him now.

Episode 4[]

The Doctor and Ben discover the bodies left by Zaroff. The two guards are dead, but Thous is wounded. They decide to take him back to the temple.

Jacko and Sean are unsure as to what to do — they are tempted to leave the Doctor to it. The Doctor returns with Thous and announces his plans. He informs them he is to flood Atlantis to stop Zaroff. He orders Jacko and Sean to move the people while he and Ben will begin the process.

Zaroff hears that workers are leaving their post due to the shortage of food — they are having to go and scavenge their own food.

Ben and the Doctor sneak into the generating station by Ben, dressed as a guard, pretending that the Doctor is his prisoner. Once inside, they knock out the scientist and make the reactor overload before heading off to Zaroff's laboratory.

Lost in the cave system, Jamie and Polly see one of the cave walls glowing luminously due to the radiation. As the wall begins to degrade, water begins to flood in. The pair need to make it to land, but the path they choose leads to a dead end.

Jacko and Sean hear the noise and decide it's time to leave. Damon joins their gang, lamenting the ruination of his life's work. As they escape, the temple is destroyed. Thous is distressed that Lolem was in there, but they are forced to push on.

Zaroff, concerned by the fluctuations caused by the Doctor, brings the mission forward. It will commence in five minutes. The Doctor enters and explains to the technicians and guards Zaroff's true plan. They desert him. Zaroff locks himself into his laboratory, saying that the Doctor and Ben will never get to him. As time passes, Ben hears the sea approaching and makes to leave. In order to make life harder for Zaroff, the Doctor cuts off his light supply. Zaroff comes out from his laboratory, armed, to switch the lights back on. Ben returns and locks Zaroff in his own laboratory, allowing Ben and the Doctor to escape.

The Doctor wants to go back to save Zaroff, but there is a rockfall blocking the way to the laboratory.

The water rises in Zaroff's laboratory. As the dial on his experiment drops to zero, he descends into the water.

In the cave, Polly and Jamie reach a ledge and Polly gives up, but Jamie convinces her to continue climbing. Soon enough, they reach the surface. Jamie tells to Polly that it is unlikely the Doctor and Ben have survived.

Also safe, Ara, Thous and Damon think the Doctor dead. Thous wants to raise a stone for him in the new temple, but Damon says there will be no temples or Fish People in the new Atlantis. He says superstition caused the trouble with Zaroff, and the restoration of Atlantis will be a memorial to the Doctor.

As Ben and the Doctor make their way up to the land, Ben wonders if Polly has survived.

On land, Polly and Jamie sit disconsolate, until the Doctor and Ben emerge from the ground. They head to the TARDIS. As they dematerialise, Jacko and Sean look on in bemusement.

In the TARDIS, Jamie admits that, without having a clue what's going on, he is enjoying himself. The crew mock the Doctor for not being able to control the TARDIS. He says that this isn't true and to prove it he will take them to Mars. He flicks a switch and the TARDIS begins to careen out of control.


Uncredited cast[]



Story notes[]

  • This story had the working titles of The Fish People, Under the Sea (also referred to as Doctor Who Under the Sea) and Atlanta.
  • Only episodes two and three of this four-part story exist in the BBC Archives as 16mm black & white film telerecordings.
  • Since Jamie isn't actually shown inside the TARDIS in The Highlanders, episode one of this story has his "bigger on the inside" moment.
  • Episode one of this serial concludes a run of twelve missing episodes, which begins with episode four of The Tenth Planet. As of 2020, this is the longest run of missing episodes.
  • At the end of episode three, Professor Zaroff utters the timeless line, "Nothing in the world can stop me now!" Davros and the Fifth Doctor would say similar lines in Journey's End and The Caves of Androzani respectively.
  • According to Anneke Wills on the DVD commentary, the main cast didn't gel with director Julia Smith: "We would mess around, and she would get more and more like a schoolteacher, so we got naughtier and naughtier. Pat would call her a 'miserable old bitch', but that's what we were like. We had power, we were the main actors. Otherwise, most of the directors we got on really well with. Only Julia had a bad time with us. We made her life a misery."
  • In the opening TARDIS scene, Polly, Ben and the Doctor are each heard "thinking" about where they would like to land next in a rare example of internal monologue. This was achieved by pre-recording the actors' voices and playing them back during the making of the episode.
  • Zaroff was at one point assisted by a female scientist called Steen.
  • Originally, there was a character named Ebon, but it was then decided to merge her with Ara.
  • In an early draft of the story, Zaroff's motivation to blow up the Earth stemmed from his being driven mad by the deaths of his wife and children in a car crash.
  • While The War Machines still remains the only time in the history of the classic series where the Doctor is referred to explicitly as "Doctor Who" (although the term also features in An Unearthly Child and The Gunfighters), the Doctor's note to Zaroff in the first episode is signed "Dr. W", making this the second closest the Doctor has ever come to referring to himself as "Doctor Who" until the Twelfth Doctor used it in World Enough and Time.
  • Since its original discovery by Ian Levine following an audit of the BBC Archives in 1977, episode three was thought to be the earliest surviving episode from the Patrick Troughton era, until episode two was recovered on 19 September 2011.
  • This was the first story about the lost city Atlantis.
  • One music cue from this story exists, entitled "The Fish People".
  • This is the final story in which the Second Doctor wears his stovepipe hat. It makes its last on-screen appearance during the closing TARDIS interior scene of episode four, when it is worn by Polly (as shown in John Cura's tele-snaps).
  • Hugh David was originally offered the chance to direct this story but he turned it down as he felt it was too expensive for the show's budget. (DCOM: A Fishy Tale)
  • Patrick Troughton was reputedly particularly unhappy about the production. He is reported to have described the show as having "ridiculous costumes and make-up of the Fish People".
  • Innes Lloyd disliked the story, admitting that "it did look like something from a '50s American 'B' movie".
  • Anneke Wills was unhappy that Polly was reduced to being a damsel in distress; she and the rest of the cast particularly disliked the infamous scene where Jamie slaps her to break her out of a mental breakdown.
  • Michael Craze said of the story: "You just knew it was a dodo. The whole thing was badly conceived — tatty old scripts and costumes and everything. It ended up as a pantomime. Julia Smith was so emotionally charged that she'd burst into tears at anything."


  • Episode one - 8.3 million viewers
  • Episode two - 7.5 million viewers
  • Episode three - 7.1 million viewers
  • Episode four - 7.0 million viewers


  • Joseph Furst adopted an outrageous East European accent in his portrayal of Zaroff. (Furst used his natural speaking voice.)

Filming locations[]

Production errors[]

If you'd like to talk about narrative problems with this story — like plot holes and things that seem to contradict other stories — please go to this episode's discontinuity discussion.
  • At the start of episode three, the director's voice can be heard.
  • During the "underwater" scene in episode three, the Kirby wires holding up the Fish People are clearly visible.
  • When Zaroff fires his pistol at the end of episode three, there is a sound effect, but no evident smoke, recoil, or discharged cartridge. The gun also changes from a Walther to a Beretta between episodes three and four.
  • In episode three, after the kidnapping of Zaroff and just before he collapses, the Doctor is seen wearing an earring (part of his Atlantean disguise from earlier that Troughton evidently forgot to remove). In the next scene after Zaroff collapses and the group splits up, the earring is no longer visible.
  • At the end of episode three, Zaroff utters "Nothing in the world can stop me now!" with eager excitement, but at the beginning of episode four, the line is uttered in a different tone.
  • In episode two, when the Doctor is trying to convince Ramo about Zaroff, an extra is clearly visible behind him. Funnily enough, the extra plays a guard who is looking for the Doctor.


Home video and audio releases[]

DVD releases[]

  • Episode three, then the only episode of the story known to exist, was released on the Lost in Time DVD in 2004. Editing of episode three's DVD release was completed by the Doctor Who Restoration Team.
  • A DVD release comprising episodes two and three plus animated reconstructions of episodes one and four was planned for release in 2014. It was postponed when the studio providing animation ceased trading and was cancelled in 2015 despite having special features and DVD cover art completed. This left episode two as the only episode of Doctor Who to exist in the BBC archive and not be released in any format on home video. The story was finally released, with telesnap reconstructions of episodes one and four (which were minus reconstructed opening title sequences, explanatory text captions, surviving clips and closing credit caption roller), on 26 October 2015.


Digital releases[]

After a DVD release of 26 October 2015, the same version was released:

  • as a stand-alone season of Doctor Who: The Classic Series in iTunes stores: first in Australia and the UK; later in Canada and the US. The season also includes the documentaries A Fishy Tale and Television Centre of the Universe (parts 1 and 2), as well as a photo gallery
  • on Amazon Video in the UK as Season 32 of Doctor Who (Classic) series, which also includes the documentaries A Fishy Tale and Television Centre of the Universe (parts 1 and 2), as well as a photo gallery.
  • Google Play lists this as "Season 8" of "Classic Doctor Who", and contains the same special features as the Amazon Video release.

Audio releases[]

External links[]