The powers of good are pitted against the forces of evil as the Duc de Richelieu wrestles with the charming but deadly Satanist, Mocata, for the soul of his friend. Mocata has the knowledge and the power to summon the forces of darkness and, as the Duc de Richelieu and his friends remain within the protected pentacle, they are subjected to ever-increasing horror until thundering hooves herald the arrival of the Angel of Death.
| Actor | Role |
|---|---|
 Christopher LeeDuc de Richleau | Duc de Richleau |
 Leon GreeneRex Van Ryn | Rex Van Ryn |
 Patrick MowerSimon Aron | Simon Aron |
 Niké ArrighiTanith Carlisle | Tanith Carlisle |
 Charles GrayMocata | Mocata |
 Sarah LawsonMarie Eaton | Marie Eaton |
 Paul EddingtonRichard Eaton | Richard Eaton |
 Patrick AllenRex Van Ryan (voice) | Rex Van Ryan (voice) |
 Rosalyn LandorPeggy Eaton | Peggy Eaton |
 Gwen Ffrangcon DaviesCountess | Countess |
 Russell WatersMalin | Malin |
 Eddie PowellThe Goat of Mendes | The Goat of Mendes |
| KKeith PyottMax | Max |
| JJeff SilkChauffeur | Chauffeur |
 Peter SwanwickSatanist | Satanist |
| JJohn TathamSatanist | Satanist |