Doctor Who and the Tenth Planet

Many aeons ago, Earth's twin planet, Mondas, drifted away to the edge of space. Its inhabitants grew weak, so their scientists created spare parts for their bodies. Limbs and organs were slowly replaced by metal and plastic, and emotions were removed. The Cybermen were born.

The TARDIS lands at the South Pole Tracking Station late in 1986, just as a routine space mission starts going wrong. When the base personnel's suspicions are raised, the Doctor informs them that the space capsule is being affected by the gravitational pull of another planet. A tenth planet...

As Mondas returns to the solar system, the Doctor warns that a visit from Mondas's inhabitants is imminent. The Cybermen want Earth's power and resources for themselves. Only the Doctor offers the base any hope against these silver giants. But is this one battle too many for the ailing time traveller?