Atlanta, GA 12/9/2010 1:17:14 AM
News / Entertainment

Doctor Who's Time Lord will be cloned by aliens in a dramatic episode of the sci-fi drama next year.

An army of monsters from outer space will make a carbon copy of the handsome doctor - who is played by Matt Smith - as they invade Earth.

However, the Time Lord will only discover the clone when he comes face to face with himself as he investigates the alien invasion, and tries to foil the extra-terrestrial beings' plans to take over the world.

His companions Amy (Karen Gillan) and Rory (Arthur Darvill) also become confused when they can't work out which is the real doctor and which is his double, and who they should be taking instructions from.

The hit BBC One series returns in the spring after its special Christmas Day (25.12.10) episode, which will be based on 'A Christmas Carol' with an alien twist.

With show boss Steven Moffat claiming the festive special is the "most exciting" episode he's ever written, the one-off show will pay homage to Charles Dickens' famous 1843 story about Ebenezer Scrooge and the ghosts of Christmases past, present and future.