I know... I know!The Doctor

The Edge of Destruction was the third story of Season 1 of Doctor Who. The story is unique for the original series in that it is set entirely inside the TARDIS and features only the regular cast members.


A mysterious blast renders the TARDIS crew unconscious. They awake disorientated and soon find that the TARDIS is strangely malfunctioning. As all the systems breakdown, the behaviour of the crew becomes more erratic. Soon the Doctor comes to believe that the school teachers are behind the malfunctions in an attempt to blackmail him into taking them home.

Gradually it becomes clear that the problems are a warning from the TARDIS. It seems that a spring has broken on the Fast Return Switch causing the TARDIS to travel back through time towards the creation of the Milky Way Galaxy. The Doctor corrects the problem and the travellers are able to escape.


The Edge of Destruction (1)

The Doctor, while attempting to correct the TARDIS's faulty navigation circuits, causes a small explosion. The Doctor, Barbara, Ian and Susan are all temporarily rendered unconscious. Barbara is the first to recover and awakens Ian and Susan, who appear to have slight cases of amnesia. The Doctor is lying on the floor with a gash on his head. Susan recovers her senses enough to retrieve a special healing bandage from the ship's first aid kit, and water from the food machine for her injured grandfather. Suddenly, Susan becomes convinced that an alien presence is on board and has seized control of the ship.

The TARDIS doors begin intermittently opening and closing of their own accord, and when Susan attempts to operate the door switch on the console, she receives an electrical shock. As the Doctor begins to revive, Barbara tends to him while Ian carries Susan to her room. There she stabs at him with a pair of scissors, rips her bed to shreds, then collapses.

Later, the Doctor, Barbara, and Ian discuss the situation, with all three alternating between clarity of mind and paranoid sniping. The Doctor checks the system controls with Ian's assistance, while Barbara checks on Susan, who has retrieved the scissors and again attempts to attack one of her teachers with them, but stops herself from doing any real harm.

When the Doctor attempts to determine their location with the view scanner, he finds only images which he recognizes as records of the TARDIS's previous journeys. The last image, an explosion, puzzles him. Susan by now is convinced that not only has an alien intelligence entered the ship, but that it has taken over one or more persons on board. When the Doctor opens the TARDIS doors, they quickly close themselves again. Because Ian happened to be standing near the switch, he is suspected of having closed them. Soon, the Doctor and Susan begin to distrust their human companions. Barbara angrily refutes the Doctor's suspicions with a recap of their recent adventure on Skaro, where she and Ian risked their lives to save the Doctor and Susan from the Daleks. Her tirade is abruptly ended when she sees the cathedral clock the Doctor keeps in the console room has melted, a sight which horrifies her.

The Doctor excuses himself from the room and returns with a tray full of drinks, a "nightcap" which he offers as a peace offering to his companions. Barbara, Susan, and Ian retire to their quarters and drink the nightcaps, not knowing that the Doctor has drugged them. With his companions knocked out, the Doctor hopes to tackle the problem of his disabled ship without interference.

Looking on his companions to confirm they are asleep, the Doctor proceeds to examine the console when a pair of hands grabs his throat...

The Brink of Disaster (2)

The Doctor's attacker is none other than Ian. A strange force has overridden the effects of the drug and compelled Ian to stop the Doctor from operating the TARDIS controls. Once Ian recognizes the Doctor, he collapses. Barbara enters and finds herself and Ian openly accused by the Doctor of sabotage.

As Barbara tries to reason with the Doctor, Susan enters the room and sides with her grandfather, but then finds herself believing in her teacher's innocence. The Doctor is threatening to put the humans off his ship when an alarm sounds. The fault locator lights up, showing faults in every system. An explosion rocks the ship. The Doctor realizes that the TARDIS's power source, located beneath the console, is trying to force its way out and they are only minutes from destruction.

Faced with a common peril, the travellers forget their differences and begin to work together. Barbara deduces that the strange events are an attempt by the TARDIS itself to warn the crew that something is wrong. The Doctor traces the problem to a broken spring in the Fast Return Switch. The malfunction is causing the TARDIS to head back to the beginning of time; the strange events were just the TARDIS's attempts to warn its passengers before the ship is destroyed. Fixing the switch brings all back to normal. The Doctor is forced to do what he least enjoys - apologise, and admit that he was wrong about Barbara and Ian.

The TARDIS materializes on a snowy landscape, where Susan spots a giant footprint in the snow...




  • The Doctor realises for the first time that the TARDIS is at least partly sentient, a fact that seems to surprise him.
  • The TARDIS has an inbuilt memory of all the locations it has previously visited.
  • Despite the size of the TARDIS Susan and Barbara share a sleeping area.
  • Susan and the Doctor share a telepathic link with each other and the TARDIS.
  • From this point, the Doctor's personality becomes somewhat mellower and friendlier, but no less crotchety.

Astronomical objects

Individuals / Cultural references


  • Susan mentions Quinnis
  • The TARDIS crew have just departed Skaro

Races and species

Story Notes


  • The Edge of Destruction - 10.4 million viewers
  • The Brink of Disaster - 9.9 million viewers


  • This story had the working title Beyond the Sun. (This was a working title used for The Daleks) (See Also: Disputed story titles).
  • This story was written at short notice because the set for Marco Polo was not complete (See notes for real reason).

Filming Locations

Discontinuity, Plot Holes, Errors

  • In the first episode, the studio floor is visible in the "white void" outside the TARDIS.
  • The Doctor tells Ian that they only have 5 minutes to survive in episode 2 - yet it takes over 5 minutes before they release the fast return switch. The Doctor even takes time to deliver a long and rather pointless speech when he knows that their end is only a few seconds away.
  • The TARDIS crew do well to spot the patterns to the TARDIS warnings - especially since they only start in episode 2 after happening randomly in episode 1.
  • William Hartnell, completely throwing the other actors during one scene by saying the same line ("It's not very likely") twice, and fumbling "You knocked both Susan and I unconscious". He also omits the scripted explanation for the melted clocks.
  • Two floor assistants' shadows can be seen in episode 1, against the door leading into the bedroom and food machine area.
  • The Fast Return Switch should have sent them back to 100,000 BC as that was the last place it visited prior to Skaro and not 1963 London. (This faux pas can be explained in several different ways. The most obvious is that the Doctor's understanding of the TARDIS at this point is apparently rudimentary, compared to what it would become in later incarnations. Since it was not he, but really a combination of Ian and Barbara, who traced the problem to the Fast Return Switch, it's easy to conclude that the First Doctor didn't really understand its functionality fully)



DVD, Video and Other Releases

TheBeginning DVD
  • DVD Release

This story was released (Doctor Who: The Edge of Destruction) together with An Unearthly Child and The Daleks on The Beginning DVD box set.


PAL - Roadshow ????
NTSC - Warner Video E2489
  • Video Release

Released as Doctor Who: The Edge of Destruction and Dr Who: The Pilot Episode as a compilation video. The BBC originally intended to release this story in a box set with An Unearthly Child and The Daleks, but they changed their plans and decided to release each story individually.


PAL - BBC Video BBCV6877
NTSC - Warner Video E1578 (2 tapes)

Notes: This video release includes the full takes of The Pilot Episode. The US release also included the documentary The Missing Years and episode 3 of The Underwater Menace.


Edge of Destruction novel
Main article: The Edge of Destruction (novelisation)

This story was first published by Target Books as Doctor Who - The Edge of Destruction, by Nigel Robinson (ISBN 0-426-20327-5) on 20th October 1988. It was number 132 in Target Books Doctor Who Library and featured cover art by Alister Pearson. It was priced £1.99 with a print run of 23,000 copies.

See also

to be added

External Links

Template:Season 1

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