Doctor Who series four is go

There will be a fourth series of Doctor Who, writer/producer Russell T Davies has confirmed, although he refused to say whether David Tennant would continue in the lead role.

Speaking at the London premiere of the third series, Davies declared: "Series four is officially existing. I'm very excited, but we have known for ages." Tennant refused to be drawn on his possible participation, telling the press: "Do you know how many times I have been asked that question? Do you know how many times I have answered it?"

Series three kicks off on BBC One on 31 March. It features Freema Agyeman as the Doc's new assistant Martha Jones, replacing Billie Piper as Rose Tyler who decided to hang up her time-travelling boots. Agyeman said: "Billie did a tremendous job. I know no one likes change but the nature of the show is change and hopefully fans will be cool with that and give me a chance."

Highlights of the new series are a Dalek two-parter and the Doctor "sharing a kiss" with Martha Jones in the first episode. Hot stuff. ®