Jon Pertwee

The Doctor

Katy Manning

Jo Grant

David Troughton

Peladon

Geoffrey Toone

Hepesh

Henry Gilbert

Torbis

Alan Bennion

Izlyr

Sonny Caldinez

Ssorg

Stuart Fell

Alpha Centauri

Ysanne Churchman

Alpha Centauri (voice)

Nick Hobbs

Aggedor

Murphy Grumbar

Arcturus

Terry Bale

Arcturus (voice)

Gordon Stothard

Grun

George Giles

Guard Captain

Wendy Danvers

Amazonia

Lennie Mayne