Jason Vane is England’s suavest secret agent, and today he’s on his deadliest mission yet. Tracking down the evil Okulov... before he destroys the world. The Doctor, Ann and K9 are, in contrast, finding their own mission a little hard to complete. A strange storm in the vortex has swept them back in time, back to Earth in 1978 and a strange place called ‘Fever Island’. A place where their worst nightmares are about to come true...