The Tardis lands on a space station orbiting Earth in the distant future. It's seemingly deserted, but the Doctor, Sarah and Harry soon discover that they are not alone. Thousands of humans are in cryogenic sleep, and while they've slept their Ark has been invaded. A parasitic insect race - the Wirrn - have taken control and threaten the very future of makind... Special Features: Commentary with Tom Baker, Elisabeth Sladen and Philip Hinchcliffe A New Frontier: Making The Ark in Space TV Movie Version..