The Doctor, his companions and the troopers are under attack by two androids that seem to be defending a hatch in the cave wall. Adric wanders out of the TARDIS and with his help the troopers manage to destroy the androids. The Doctor and Adric open the hatch to discover a bomb. They deactivate it but a source of transmission is coming from somewhere. The Doctor's enemy, the Cybermen, are behind the plantation of bomb. Meanwhile, in outer space, a freighter is being inspected by Earth security forces while replenishing its supplies and crew. The TARDIS materializes on board, but murders have also been occurring on board the freighter.