Doctor Who (1963) Season 21 Episode 17 Planet of Fire (3)

The Doctor finds himself on the planet Sarn, where he encounters an old foe, the Master, who is masquerading as the religious leader of a group of native people. Meanwhile, Turlough struggles with his emotions as he is forced to confront his past and his loyalty to the Doctor is tested. As they delve deeper into the mystery surrounding the planet, they uncover a dangerous plot to harness the planet's power for selfish gain. With time running out, the Doctor and his companions must race to stop the Master and save Sarn from destruction. Along the way, they encounter new allies and face unforeseen challenges, testing their abilities and determination to protect the universe.