When a Thal platoon arrive on a hostile planet investigating reports that Dalek artefacts have been detected, they are unprepared for what they find. In an underground room is a stranger, a Professor, or so he claims, with no memory of who he is or why he is there.
With death and horror their only companions, the Thals make their way with the Professor into the heart of a crumbling Dalek citadel in search of answers … only to find that the Daleks are the least of the horrors they must face.