Jo Grant is shocked to find most of her colleagues are missing.
Then she discovers that the Doctor has inexplicably changed.But there's little time to worry about it all, as she and her misplaced Time Lord friend are whisked to the mysterious Delphin Isle on a matter of national security.
There, they encounter a disturbingly odd form of local hospitality and learn of a highly classified incident that took place during the Cold War.
Why exactly have they been brought here? And what is the truth concerning the bodies in the harbour and the vast project being undertaken under a cloak of secrecy?
The first of a trilogy of stories putting later Doctors in earlier roles, a special event marking Big Finish's two hundredth main range Doctor Who story.
Sylvester McCoy has recently been seen as Radagast the Brown in the big-screen films of The Hobbit series.
CAST: Sylvester McCoy (The Doctor), Katy Manning (Jo Grant), Richard Franklin (Captain Yates), Neil Roberts (Captain Cornelius), Barnaby Edwards (Commander Wingford), David Graham (Shedgerton), Rachel Bavidge (Europan Leader), Jez Fielder (Europan) .