The Seeds of Doom: Part One

Members of the World Ecology Bureau discover a centuries-old seed pod buried deep in Antarctica's permafrost. It seems to be still alive, growing without soil. They transmit a photo to London where Richard Dunbar of the W.E.B. shares it with the Doctor. Wary of what it might be, the Doctor immediately flies down with Sarah. They don't know that Dunbar is a leak in the...