The BBC has announced that 21-year-old relatively unknown actress Karen Gillan will step into the TARDIS as the companion in “Doctor Who” when Matt Smith takes over as the 11th Doctor in 2010.
Gillan has already appeared in “Doctor Who,” portraying a soothsayer in the season four episode, “The Fires of Pompeii.”
Executive Producer and Head of Drama BBC Wales Piers Wenger said, ‘We knew Karen was perfect for the role the moment we saw her. She brought an energy and excitement to the part that was just fantastic. And when she auditioned alongside Matt we knew we had something special.’
Meanwhile, current Doctor, David Tennant, will star in three more “Doctor Who” specials to air later this year before Smith takes over the role.
Tennant will be the new host of PBS’ “Masterpiece Contemporary” series when it returns in October.
Tandem With The Random 
its going to be wierd not to have david tennant and rose or donnor or martha , david tennant is gorgeous no affence to matt smith , and the new episodes are worth looking forward too .