Dr Who: Meglos

On the planet Tigella, the mysterious source of all power - the Dodecahedron - is failing. Zastor, the leader of the planet, decides to call on an old friend to help them. An old friend who travels the universe in a blue police box... On a nearby dead planet of Zolfa-Thura, a rag-tag band of space raiders form an uneasy alliance with the cactus-like alien, Meglos. Their goal is to prvent a certain Time Lord from arriving on Teglia... Aboard the TARDIS, the Doctor, Romana and K9 find themselves trapped in a chronic Hysterisis - a time loop that keeps them captive in the same few minutes in time again, again and again. And double trouble awaits them on Tregella... Originally Transmitted 27th September - 18th October 1980