Both TARDISes reach Atlantis, where the Doctor befriends King Dalios while the Master enlists the help of Queen Galleia to try and obtain the crystal of Kronos.
Quest roles:
Ingrid Pitt(Galleia), Roger Delgado(The Master), Michael Walker(Miseus), Donald Eccles(Krasis), Aidan Murphy(Hippias), George Cormack(Dalios), Derek Murcott(Crito), Susan Penhaligon(Lakis), David Prowse(Minotaur), Melville Jones(Guard)