Doctor Who, it has been confirmed.
The 62-year-old actor, who played the fifth incarnation of the Doctor between 1981 and 1984, is set to join Matt Smith and other stars at a three-day event being staged by the BBC at ExCel London.
Taking place from 22 to 24 November, the event will also see appearances from former Doctors Tom Baker, Colin Baker and Sylvester McCoy.
[uuid=473f38a6-697e-4763-bee1-53d4cbd646b5]The show's 50th anniversary special[/uuid] episode, The Day Of The Doctor, will be screened during the event on 23 November - with tickets being allocated on a first-come-first-served basis to attendees.
A host of writers, production staff and former stars will be appearing at the event - and full details are available at http://celebration.doctorwho.tv/