As the logic tests allowing passage further into the Exxilon City become more devious, the Doctor and Bellal have to be more cautious. The Daleks, on the other hand, power through the puzzles and traps with a combination of brute force and their rapidly-calculating battle computers. The Doctor and Bellal reach what appears to be the end of their journey – the city’s control room. The Doctor sets about dismantling the primary computer “brain” of the city, while the city retaliates by slowly materializing zombie-like “antibodies” to destroy the interlopers – whether they’re flesh and blood or Daleks. Sarah reaches Jill Tarrant, one of the surviving crew of the Earth ship, and begins planning to double-cross the Daleks, loading all of the needed substance aboard the Earth ship while the Daleks end up with bags of sand. When the city begins to self-destruct, the Daleks regain all of their deadly powers…but one of their human prisoners has a final trick up his sleeve.
written by Terry Nation
directed by Michael Bryant
music by Carey Blyton and played by the London Saxophone Quartet
Cast: Jon Pertwee (The Doctor), Elisabeth Sladen (Sarah Jane Smith), Duncan Lamont (Dan Galloway), John Abineri (Richard Railton), Neil Seiler (Commander Stewart), Julian Fox (Peter Hamilton), Joy Harrison (Jill Tarrant), Arnold Yarrow (Bellal), Michael Wisher (Dalek voices), John Scott Martin (Dalek), Cy Town (Dalek), Murphy Grunbar (Dalek), Steven Ismay (Zombie), Terry Walsh (Zombie)
LogBook entry by Earl Green