Written by Douglas Adams. This four-episode serial first aired from September 30 to October 21, 1978.
The search for the Key to Time takes the Doctor and Romana to Calufrax. The coordinates are right, but it's too warm and inviting a world to be Calufrax. In fact, the TARDIS lands them on Zanak, the World of Ham. But the Tracer is going berserk — it's sensing the second Key to Time segment everywhere.
It turns out that the planet Zanak has been hollowed out and fitted with engines, and is now piloted by the demented Captain. While, sadly, this magnificently Large Ham may not be portrayed by BRIAN BLESSED, he is, instead, a Hollywood Cyborg, always accompanied by a rather stoic nursemaid. His job is to teleport Zanak into position around other planets, suck them dry and mount the shrivelled and supercompressed husks in a trophy room.
The nursemaid turns out to be the real brains behind the operation, a holographic projection of Zanak's Queen Xanxia, using time dams and the forces generated by the trophy room to remain young. The Captain announces that Zanak's next target is Earth, and the Doctor enlists the telekinetic help of La Résistance — the native Mentiads — to sabotage the engines by simply throwing a spanner into them. The Captain rebels and is killed by Xanxia, whose avatar is in turn killed by one of the natives. The Doctor and the Mentiads then blow up the bridge, killing the real Xanxia.
The Doctor realises that the segment of the Key to Time he is after is in fact the entire planet Calufrax, now conveniently shrunk to a rather more manageable size.
- An Aesop: The Doctor provides one for Romana when he realizes that the Captain was hiding his cunning mind from Xanxia with his Large Ham tendencies:"Let that be a lesson for you girl. Never take anything at face value."
- Animal Mecha: Besides K-9, the Captain has an avian-looking killer robot.
- Batman Grabs a Gun: Romana shoots an enemy soldier dead. Although her predecessor, Leela, often used deadly force, this was one of the only on-screen occasions in which Romana did so. Romana's reaction to doing so leaves it unclear as to whether this is the first time she's killed someone.
- Beware the Silly Ones: The Fourth Doctor explodes into a rage far more violently than he ever had before or after, and perhaps even more so than any other Doctor. It is horrifying... but also incredibly glorious.
- Blofeld Ploy: The Captain berates Mr. Fibuli for not having figured out the Negative Space Wedgie from earlier in the episode. "When someone fails me," he declares, "someone DIES!" With that, his mechanical bird thingy arises... and kills a different underling. He then assigns the same task to Fibuli, violating the Evil Overlord List again.
- Borrowed Catchphrase: It's Romana who offers someone jelly babies in this story. The Doctor is not amused.
- Brick Joke: Early in the first episode, the Doctor uses the phrase "Piece of cake", which K9 misunderstands (see Expospeak Gag below). Toward the end of the final episode, when the Doctor asks what they should do about the Bridge and the time dams, K9 answers, "Piece of cake, Master, blow them up."
- Chewing the Scenery: Good God. The Scenery is simply one massive banquet for the entire cast to eat.
- Clarke's Third Law: At one point, the Captain reminisces about his old ship."The greatest raiding cruiser ever built. And I built it, Mister Fibuli, I built it with technology so far advanced you would not be able to distinguish it from magic."
- Commonplace Rare: The Captain decides to take Zanak to Earth to mine a rare mineral that is necessary to repair the engines. What mineral? Quartz.
- Continuity Nod:
- While unconscious on the Bridge, the Doctor mumbles "No more Janis thorns", a reference to Leela.
- The Doctor once again tells Romana not to trust "gimmicky gadgets".
- Cyborg: The Captain's left half is almost completely robotic.
- Dark Lord on Life Support: Queen Xanxia, who relies on time dams to keep her extremely aged physical body alive.
- Deconstructor Fleet: Douglas Adams explicitly gave the Captain some actually specific purpose for his villainy rather than putting it down to some vague "powerlust" or the like.
- Digital Avatar: The nurse.
- The Dog Was the Mastermind: The true ruler of Zanak is not the Captain, but the Captain's Nurse, the former Queen Xanxia.
- Dragon with an Agenda: In Part 4, the Captain is revealed as this. He created his "trophy room" to use the combined gravitational force of the destroyed planets to gain enough power to free himself of Xanxia's control.
- Earth-Shattering Kaboom: The eponymous planet destroys other worlds by materialising around them, stripping them of their resources and shrinking them down to the size of a basketball, after which they are displayed in the captain's trophy room.
- Eternal Engine: The story features a planet that exploitatively harvests raw materials. The Doctor must undertake some very risky maneuvers in order to shut it down.
- Even Evil Has Loved Ones: The Captain is very upset by the deaths of his metal death parrot and his favourite Mook, vowing to avenge them.
- Evil Is Hammy: The captain, of course, but as soon as Queen Xanxia drops her cover, her ham content doubles instantly.
- Evil Laugh: Subverted. The Doctor is made to Walk the Plank to his apparent death, and the villains all have an evil laugh...only to stop when they hear the Doctor laughing along with them.
- Evil Old Folks: Xanxia's true form is a frail old woman who relies on time dams to stay alive.
- Explain, Explain... Oh, Crap!: The Captain uses his technology to loot the planet Calufrax and has constructed a psychic-jamming device to defeat the telepathic Mentiads. The Doctor insists that the device can't work because it requires very rare minerals to supply power.
- The Doctor: And as far as I know, they occur naturally on only one planet, and that's...
Fibuli: Captain, the crystals from Calufrax.
The Doctor: Calufrax! ...My biorhythms must be at an all-time low.
- Expospeak Gag: The Doctor and K9 at the beginning of the first episode, when the Doctor insists that gathering the rest of the segments to the Key to Time will be a "piece of cake":K9: Piece of cake. Radial segment of baked confection. Coefficient and relevance to the Key of Time, zero.
- Because Douglas Adams wrote this serial at the same time as The Hitchhiker's Guide to the Galaxy (1978) radio series, the Captain is very similar to Prostetnic Vogon Jeltz.
- Mr. Fibuli is a Shout-Out to Mr. Bones from Treasure Island. He's named after the fibula, one of the bones of the lower leg.note
- Failure Is the Only Option: Failure becomes the only option for the villains in the last episode, when the Captain announces that they intend to consume an Insignificant Little Blue Planet...
- The Doctor tells Xanxia that her ultimate goal is impossible to complete.
- Flying Car: Aircars!
- Foreshadowing: The Captain screams and rants at pretty much everyone and everything around him except the nurse - a big clue that she's not who she appears to be.
- Good Cannot Comprehend Evil: The Mentiads' stated reason for not deposing the Captain sooner.
- Historical In-Joke: In a throwaway gag, the Doctor reveals he told Newton about gravitation after throwing an apple on Newton's head.
- Immortality Immorality: Xanxia's time dams require large amounts of energy to function, so she directs her minions to sacrifice entire planets to provide energy.
- Incoming Ham: The very first line, in fact.
- It's All About Me: Xanxia has destroyed entire planets (some of them inhabited) in the name of keeping herself alive, using a plan that the Doctor states won't actually work.
- Large Ham: The Captain, gloriously so!
- The Captain's bluster and braggadocio are part of his gambit to overthrow the Queen and shake off her not-quite-mind control.
- Well, hellllllllooooooooo Tom Baker. How good it is to see you losing all of your shit...
- Mind over Matter: The Mentiads can do telekinesis.
- Mood Whiplash: The story is a goofy, playful, high-Camp romp with enormously over-the-top Space Pirates as villains, all Played for Laughs. Until the moment when the Doctor finds out how pointlessly, selfishly evil the pirates actually are, and absolutely blows his top in a scene that is played perfectly straight.
- There is also a scene where Romana is forced to shoot and kill a pursuer, which passes quickly but also doesn't fit the mood of the overall story.
- Mundane Solution: Hit it with a spanner! (albeit telekinetically)
- Also taking out the Bridge by blowing it up.Romana: Isn't that a bit crude?Doctor: Well - it's a bit crude, but immensely satisfying.
- Also taking out the Bridge by blowing it up.
- The Necrocracy: Xanxia is the secretly undead secret ruler of a nation.
- Not Now, Kiddo: K-9, over and over again.
- Obfuscating Ham: The Captain.
- OOC Is Serious Business: We've seen the Fourth Doctor jovial and flippant in the face of evil, though he knew when to be serious. This is one of the few times he ever got really angry at an atrocity.
- Pin-Pulling Teeth: The Doctor imitates this with a bag of licqourice allsorts.
- Pirate Booty: In a very... creative way.
- Pirate Parrot: The Captain has a robot parrot with a blaster in its beak (the Polyphase Aviatron). It is destroyed off-screen by K9 (who then returns with the bird in its "mouth". Good dog!) According to Douglas Adams, he submitted that script to the production office, and it was rejected. He later wrote in the robot parrot and re-submitted it, and it was accepted.
- Powered by a Forsaken Child: Zanak's resources are gained through the wholesale mining and destruction of other planets. Said planets' inhabitants are collateral damage.
- Psychic Powers: The Mentiads, thanks to a shared Hive Mind that uses the Life Energy of the dying worlds Zanak engulfs.
- Rage-Breaking Point: The Doctor demonstrates bloodcurdling anger when he is asked to appreciate the idea of mass murder.
- Read the Freaking Manual: The Doctor has apparently owned his TARDIS for over 500 years, and has never once read it, something he points out while Romana is doing so.
- Rock Beats Laser: When faced with a locked door, the Doctor tries the Sonic Screwdriver, which fails. So he pulls out a bobby-pin, which succeeds. Quoth the Doctor: "The more sophisticated a technology, the more vulnerable it is to primitive attack."
- Shoot the Messenger: The Captain kills a guard who brings the news that the Doctor has escaped.
- Self-Plagiarism: Given that this was written by Douglas Adams, there are references to The Hitchhiker's Guide to the Galaxy (1978):
- The Doctor says "Don't Panic".
- The name "Bantraginus V" is likely a reference to "Santraginus V", the home for one of the key ingredients in the Pan Galactic Gargle Blaster.
- The Doctor's line "Standing around all day looking tough must be very wearing on the nerves".
- Space Pirates: In glorious type 2 fashion.
- Spanner in the Works: Literally.
- Calufrax turns out to be this to the Captain's plan; it might have worked if Calufrax had not turned out to be the 2nd segment of the Key To Time.
- Spoon Bending: Referenced when the Doctor needs to maintain a distinctive mental image so that the Mentiads can keep track of his location, and chooses the image of a bent fork.Romana: Why should anyone want to bend a fork?
Doctor: I haven't the vaguest idea.
- Stuff Blowing Up: Lampshaded:Romana: What about the Bridge and the time dams?
Doctor: Bridge and time dams, K9?
K9: Piece of cake, master. Blow them up.
Romana: Isn't that a bit crude?
Doctor: Well - it's a bit crude, but immensely satisfying.
- Symbolic Mutilation: The Pirate Captain. His body is largely robotic and he is gaining material wealth ruthlessly, replacing his humanity with materials.
- Tele-Frag: This would happen if two spaceships were to try to materialize in the same spot, on the same time. Though it takes a significant time, and does not actually happen during the serial.
- Trail Of Jellybabies: Used twice to lure a guard away from the Aircar, with mixed results.
- Too Fast to Stop: The conveyor floor normally stops inertia to avoid this trope. The Doctor turns it off to stop some pursuing guards.
- Two-Headed Coin: The Doctor uses one to settle a disagreement; it's legal tender from a planet ruled by two kings.
- Villains Do The Dirty Work: A variation. After preventing Zanak from destroying the Earth, Romana asks the Doctor what they should do about Zanak. The Doctor answers, "I think we should use the Captain's plan." The Captain created the technology to compress the planets Zanak destroyed so he could harness their gravitational forces as part of his long-term plans. The Doctor simply used that tech to place Zanak in permanent orbit around it's current star and to retrieve Callufrax for the Key of Time.
- Walk the Plank: But no water at the bottom, but hard rock. The Captain wishes to invoke the Disney Villain Death trope on plank-walkers. In the show, The Doctor escapes by having a hologram walk the plank. In the novelization, The Doctor does walk the plank because he didn't remember he had a hologram projector on him until it was too late, but was rescued by Romana in an epic but likely too expensive to film scene in which she pilots the TARDIS into the hollowed out core of Zanak and catches him in midair.
- Who Wants to Live Forever?: Xanxia's means are both evil and not indefinitely sustainable due to diminishing returns. The time dams storing her dying body don't stop time, only slow it. And the more time passes in the dams, the more the remaining time needs to be slowed to keep her alive. And in order to decrease the rate at which time passed in the dams, she needed more power, which meant consuming more and more planets. The Doctor flat out states that there isn't enough energy in the galaxy to truly achieve immortality using that method.
- Wicked Witch: Xanxia doesn't have any magical powers, but her method of keeping herself alive, her real body's withered, decrepit appearance, and her mannerisms all hit the right notes.
- The Woman Behind the Man: That rather nice nurse? She's actually the boss of the operation.
- World of Ham: One of the most outlandish and over-the-top stories in the show's history. Diamanda Hagan said that if this story were a person, it would be BRIAN BLESSED.
- Worthless Yellow Rocks: Whenever a new Age of Prosperity occurs, valuable gems fall from the sky. After a century or more of this, many of them are simply left lying in the streets.
- You Have Failed Me: The Captain hisses "When someone fails me, Mr. Fibuli, someone dies!" — then kills a random extra instead of the person who actually failed, because he's the Captain's right-hand man and is too useful to kill just out of pique. Of course, the Evil Overlord List specifically says not to do this, but the Captain is just too awesome to care.