Matt Smith and Karen Gillan are to return to computer screens as Doctor Who and Amy Pond with a Christmas Day special to conclude Doctor Who: The Adventure Games' current batch of episodes.
The download will be made available from the BBC website as soon as its BBC One television counterpart finishes broadcasting on December 25.
This, the fourth and final episode in the game's series, marks the return of the Vashta Nerada creatures, introduced in the 2008 TV episode "Silence in the Library."
The series' executive producer, Steven Moffat, said that the game let them do something that would be impossible for the TV series. "We've gone all-out for the season finale. Shadows of the Vashta Nerada takes place entirely underwater," something that would be altogether too expensive for a television production.
Episode 4, Shadows of the Vashta Nerada, will be free to those within the UK and made available to international fans on the same day. Previous episodes cost $5 / €4 each.