When the Doctors past and present are summoned back to Gallifrey, they are told their past is in danger - can they save themselves before the darkness of a new past corrodes their souls and changes who they are in their very core...? Featuring Doctors 6 to 12, including 10, and War along with River Song, Clara, Donna, Jack Harkness, Charley Pollard, Ace, Hex, Melanie Bush and more!