The Testament of Arkadia. Season 1, Episode 23. First broadcast Thursday 12 February 1976.

Stranded in a cold and purposeless corner of an indifferent universe, adjacent to the end of everything, the crew of Moonbase Alpha make a discovery which changes the meaning not just of their journey but of their very existence, a discovery which drives this week’s Large Hot Italian Guest Star and his posh new girlfriend to make an irrevocable decision.