The final segment of the Key to Time is at the heart of a devastating war between neighbouring planets Atrios and Zeos. The Fourth Doctor discovers that a sinister entity is manipulating events and the cost of obtaining the final segment may be more personal than he imagined.
The Doctor
Romana
K-9 (voice)
Marshal
Princess Astra
Shapp
Merak
'Hero'
'Heroine'
Guard
Technician
Pilot
Guard
The Shadow
Drax
The Black Guardian
