The Doctor's trial continues. The Valeyard's next piece of evidence for the prosecution concerns the Doctor's recent trip to Thoros Beta. Though originally investigating arms dealing, the Doctor and Peri become embroiled in their old enemy Sil's alarming neurological experiments...
Quest roles:
Lynda Bellingham(The Inquisitor), Michael Jayston(The Valeyard), Christopher Ryan(Kiv), Brian Blessed(King Yrcanos), Trevor Laird(Frax), Patrick Ryecart(Crozier), Alibe Parsons(Matrona Kani), Nabil Shaban(Sil)