Friday, 2nd March 1984 6:40PM BBC 1 (24 mins)
A volcanic eruption is threatening to destroy the inhabitants of Sarn, the Doctor manages to stabalise the seismic events but for how long? Turlough faces an agonising decision about whether to contact his home planet of Trion for help, he explains that he was sent away to Earth as an outlaw. Finally, before they can escape, the Doctor must confront the Master.