As plague sweeps 17th century England, the Doctor discovers a more exotic threat at work - shipwrecked Terileptil convicts, intent on making the planet their own.

Anthony Calf (Charles), Eric Dodson (Headman), James Charlton (Miller), John Baker, John Savident (The Squire), Michael Melia (Terileptil), Michael Robbins (Richard Mace), Neil West (Poacher), Peter Van Dissel, Valerie Fyfer (Elizabeth)