The investigation into an elaborate suicide leads Barnaby to suspect the dead man may have had help pulling the trigger.
A voice comes through from Earth. With it, the hope of return to their own planet at last for the occupants of the runaway Moon and the end of their long journey through space but the space-wandering Alphans find themselves lost in the midst of time.
Maggie questions her marriage when Neil is accused of indecent conduct.
The Doctor returns to Gallifrey, only to discover that a deadly game banned and derelict for centuries, has been reactivated. Soon he finds his other selves have also been summoned to assist him in tracing the culprit and tracking down the mysterious secret of Rassilon...
The Master and the Doctor fight for control over Kamelion's mind while Turlough and Tegan make new allies in the castle in an attempt to avoid the iron maiden.