On the lush planet Tigella, two opposing factions are divided over the usage of the Dodecahedron, an ancient and powerful artefact which provides the entire planet's energy. The Doctor is summoned to arbitrate the conflict, but the power-crazed Meglos intercepts the call and impersonates him in order to steal the Dodecahedron.

Genres

Cast

Tom Baker

The Doctor / Meglos

Lalla Ward

Romana II

John Leeson

K9 (voice)

Bill Fraser

General Grugger

Edward Underdown

Zastor

Jacqueline Hill

Lexa