Still trapped in E-Space, the Doctor, Romana, Adric and K9 encounter a medieval civilisation dominated by the Three Who Rule, vampires who govern from their mighty castle.
| Actor | Role |
|---|---|
 Tom BakerThe Doctor | The Doctor |
 Lalla WardRomana | Romana |
 Matthew WaterhouseAdric | Adric |
 John LeesonK9 (voice) | K9 (voice) |
 Emrys JamesAukon | Aukon |
 Rachel DaviesCamilla | Camilla |
| WWilliam LindsayZargo | Zargo |
 Clinton GreynIvo | Ivo |
 Rhoda LewisMarta | Marta |
| TThane BettanyTarak | Tarak |
| IIain RattrayHabris | Habris |
 Arthur HewlettKalmar | Kalmar |
| SStacy DaviesVeros | Veros |
| DDean AllenKarl | Karl |
| SStuart FellRoga | Roga |
| SStuart BlakeZoldaz | Zoldaz |