Broadcast: Thursday 25th December 2014
1:00am-2:20am EST (06:00 GMT) < > « »
BBC America (adverts during broadcast)

Featuring: David Tennant, Dervla Kirwan, David Morrissey, Velile Tshabalala

When the Doctor investigates a spate of mysterious deaths, he's surprised to meet another Doctor. The two must combine forces to defeat a human ally to the Cybermen. But are two Doctors enough to stop the rise of the CyberKing?
Synopsis Source: BBC America website schedule listing