Doctor Who and the Argonauts—katabasis for Tom Baker (again)
Doctor Who: Underworld (Serial 4Z), Four episodes, 7‒28 January 1978
Plot summary: The TARDIS materialises at the edge of the universe, where planets are being formed, and encounters the R1C, a ship of the Minyans, searching for a lost Minyan vessel, the P7E, and the Minyan race banks it carried. After narrowly escaping becoming the core of a newly-formed planet, the Doctor and the Minyans find the P7E at the core of another planet. Unfortunately, the P7E’s controlling computer has gone mad, and oppresses the surviving descendants of its original crew. The Doctor helps the Minyans of the R1C save the surviving Minyans and recover their race banks, and destroy the Oracle.
Crew: Writers: Bob Baker and Dave Martin; Director: Norman Stewart; Script Editor: Anthony Read; Producer: Graham Williams