In her mid-20s, Angie is interviewed as she tries to understand how and why her brother David committed dark and terrible deeds, which led to him being sectioned.
Vera Atkins' files were kept sealed until after she died, but the story of the female spies and the spy-mistress who led them, which has remained secret for over 50 years, can now be revealed.
Isobel and Nikolaus are now living together for three years. But two new strange neighbors, Hevn and Miley, move in the building. As Maykel comes back with Greg, who mysteriously forgot some parts of his own past, the two neighbors become weirder.
