This is taken from the BBC website. Thanks BBC :)
Corrie actress to guest star in Series Four premiere.
Sarah Lancashire, best known for roles in Coronation Street, Clocking Off and Rose and Maloney, is set to guest star in the fourth series of Doctor Who.
Sarah will play Miss Foster, an enigmatic and powerful businesswoman, in episode one, written by Russell T Davies.
"I'm absolutely thrilled to be in Doctor Who," said Sarah. "It's a brilliant episode and I'm looking forward to taking the Time Lord on."