Doctor Who 1963 - Season 18, Episode 19: Warriors' Gate: Part Three
We offer again season 18, where more powerful and diverse events are reported. The season begins when the doctor, Romana and K-9 arrive at the Tygella forest planet, where the Tiglians now live in an underground city, due to carnivorous plants. Where the doctor finds that he was wrongly accused of stealing Dodechedron, the city's energy source. Just to discover the culprit is Meglos, the last survivor resembles the cactus of the desert planet Zolfa-Thura. He offers to return Dodechedron to Zolfa-Thura for his evil purpose and plans to use it as a powerful weapon and plans to clear Tigilla.