In the distant future, the Doctor, Sarah and Harry find a space station preserving the future of mankind. But the insect Wirrn have got there first...
as The Doctor
as Sarah Jane Smith
as Harry Sullivan
as Vira
as Noah
as Rogin
as Lycett
as Libri
as The Wirrn
as The Wirrn
as High Minister (voice)
as Voices on Nerva (voice)