The TARDIS is attacked by the renegade Time-Lord the Rani (Kate O’Mara) and crash-lands on the planet Lakertya. Apparently injured in the crash, the Sixth Doctor dies and regenerates into the Seventh (Sylvester McCoy). Confused after regeneration, he is separated from his companion Melanie Bush (Bonnie Langford) and tricked into helping the Rani build a giant Time Manipulator in her latest scheme to dominate the universe. When last we saw her, she was trapped in her out-of-control TARDIS with a growing young Tyrannosaur, but we are not told how she escaped being Cretaceous lunch.
Mel is lost on the barren planetary surface and must avoid the Rani’s booby-traps and monstrous four-eyed bat-like servants, the Tetraps from the planet Tetrapyrianbus. She joins the Lakertyan rebels, who are trying to end the Rani’s control of their planet. Mel has already perfected the companion’s two main jobs, joining the revolution, and screaming in terror.
The Rani has collected from throughout time the greatest scientific minds of the universe, including Albert Einstein, Louis Pasteur, and Hypatia, Chief Librarian of the ancient Library of Alexandria, in order to help create her time manipulator, which would give her the power to control time throughout the universe, and now she can add the Doctor to her staff. She will use an asteroid of strange matter to form a shell around Lakertyia, causing an artificial brain in her possession to expand and fill the entire surface of the planet, unfortunately wiping out all life.
As the Doctor regains consciousness, she injects him with an amnesia-producing drug and disguises herself as Mel. The Doctor regains his wits and eventually foils her plans. The Lakertyans are freed. The Rani escapes in her TARDIS, but it has been commandeered by the Tetraps and she becomes their prisoner. The Doctor begins to return all the geniuses to their own time-zones.
The first Sylvester McCoy story proceeded at breakneck speed with driving and percussive background music, but according to script-editor Andrew Cartmel, was somewhat lacking in depth. One of the problems was that writers Pip and Jane Baker had no idea who would be playing the Doctor and what he was like. There was a new opening title sequence created on a synthesiser, with new electronic music by Keff McCulloch. It has been suggested that the BBC had already given up on Doctor Who but needed something to sacrifice opposite Coronation Street.
As the Sixth Doctor, Colin Baker—smarting from being summarily fired—declined to appear in the regeneration sequence, Sylvester McCoy had to put on the Sixth Doctor’s oversized, garish costume and a Harpo Marx wig, and collapse behind the TARDIS console, then appear as himself. Trying on clothes, he sheds Colin Baker’s absurd costume, tries on the hat and scarf of Tom Baker, the frilled shirt and smoking jacket of Jon Pertwee, the cricket-inspired outfit of Peter Davison, and the huge fur coat of Patrick Troughton, before appearing in his own signature costume.
Sylvester McCoy was criticized as a lightweight Doctor. He was a children’s television actor and a circus entertainer, which is obvious throughout his tenure. Later, he would reveal flashes of comedic brilliance, with a touch of Patrick Troughton, Tom Baker, and some have said, Charlie Chaplin. I think of him as the Stan Laurel to Colin Baker’s Oliver Hardy. Kate O’Mara was a pretty good queen bitch evil Time-Lord. After all, she had held her own against Joan Collins on Dynasty. A highlight of the less-than-stellar story is her pretending to be the cheerful and bubbly former child-star Bonny Langford, playing Mel to McCoy’s exasperating Doctor.