The orbit of Jupiter, the 25th century. Sarah Jane falls victim to the same plague as the other Nerva crewmen. With time running out, the Doctor transmats her and Harry down to the planet Voga, unaware that a mysterious ship is approaching the beacon.
Elenco:
William Hartnell
,
Patrick Troughton
,
Jon Pertwee
,
Tom Baker
,
Peter Davison
,
Colin Baker
,
Sylvester McCoy
.