Doctor Who: The Impossible Astronaut

The Doctor and his friends are reunited under mysterious circumstances, as the science-fiction drama returns for a new series. Amy, Rory, River and the Doctor receive a series of numbered envelopes, each containing a date, time and map reference. These messages bring them together in the middle of the Utah desert, where the Doctor's friends learn a terrible secret that must be kept from the Time Lord at all costs. But who sent the envelopes, and who received the missing number one? Their quest for answers takes the TARDIS crew to the Oval Office, where President Richard Nixon enlists their help in saving a terrified little girl from a mysterious spaceman...