Nyssa will die at dawn, and the Doctor doesn't even know why.
To save her life, he must make a desperate journey to the only place in the universe where a cure might exist.
When even that fails, the Doctor has a choice - let Nyssa die, or make a deal with the devil.
After all, the road to hell is paved with good intentions...
Written By: Lance Parkin
Directed By: Gary Russell
Peter Davison (The Doctor); Sarah Sutton (Nyssa); Susan Penhaligon (Shayla); Stephen Greif (Kwundaar); Ian Hallard (Sabian); Romy Tennant (Anona); Rita Davies (Janneus); Mark Woolgar (Hyrca); Billy Miller (Narthex / Captain Kabe); Alistair Lock (Etrayk)