Saturday 23rd June at 6:15pm (BBC1)
The evil Mr Harold 'Harry' Saxon becomes Prime Minister, and it's not long before his reign of terror begins. But this is only the start of Saxon's ambitious plans as he announces mankind's first contact with an alien race, the Toclafane.
At that moment, an audacious plan – spanning the whole of time and space – begins to close around the Earth. Can the Doctor and Martha prevent Planet Earth from entering its darkest days?
Life On Mars actor John Simm guest stars.
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