Crospa was a Traveller, native to Epajaenda. His people had left the planet, based on an agreement with Abraham Derris-Cuthbertson, and returned to find it being prepared as a waste dump.
Crospa entertained the Seventh Doctor and Ace in the Epajaenda spaceport.
Despite the Doctor's scepticism, Crospa remained optimistic that Derris-Cuthbertson would honour his agreement. Crospa and his fellow Travellers were delighted when Derris-Cuthbertson returned at last and turned the planet over to them, after cleaning it. (PROSE: Last Rites)