5. Ben Miller
ITV StudiosNot content that his frequent collaborating partner Alexander Armstrong has had two separate roles on Doctor Who (the voice of supercomputer Mr. Smith and fighter pilot Reg Arwell), it now seems that comedian Ben Miller also has his own turn to appear on the show. Originally known for his comedy roles, particularly in films such as Johnny English and The Parole Officer, Miller is no stranger to British science-fiction, having appeared in all five series of Primeval. More recently he has been seen in (slightly) more dramatic roles in Noel Clarke's 4.3.2.1., and Death In Paradise. The BBC announcement states that, like Tom Riley, Miller will be appearing in an episode written by Mark Gatiss, and a quote from Moffat gives very strong hints as to his character: "Mark Gatiss has written us a storming villain for his new episode, and with Capaldi in the TARDIS, we knew we needed somebody special to send everybody behind the sofa." Although only speculation at this point, it could therefore be reasoned that Miller will soon be seen Sheriffing the town of Nottingham.