Comedian Peter Kay is to appear in the second series of the new 'Doctor Who'.

He will play Victor Kennedy, a character described as "cold and powerful".

Kay was cast in the series after writing a fan letter to 'Doctor Who' writer Russell T Davies.

"Casting of Peter came about after he wrote me the most brilliant letter to say how much he'd enjoyed series one of 'Doctor Who'," said Davies. "From that point on we started talking about a guest appearance."

Kay will appear in the 10th episode of the new series, which begins on BBC 1 this spring.