This final, six-part, instalment of the "Key to Time" series splits quite neatly into two stories, really. The first sees our travelling Time Lord (Tom Baker) and his colleague "Romana" (Mary Tamm) arrive on the planet of "Atrios" right in the middle of their war with the neighbouring "Zeos". Thus far it's proved a bit of a stalemate, but the "Marshal" (John Woodvine) reckons he has a plan that wiver mais...