Family mysteries

Maggie is sitting alone in the park when she’s approached by Harvey, who introduces himself as a recruiter for MI5. This is the starting point of Mick Herron’s This is What Happened (John Murray, £16.99). The company Maggie works for is under investigation as a possible threat to national security. She takes on a task, to feed a virus into the company’s computer network, but during this operation she accidentally kills a security guard. Harvey places her in a safe house. No windows, a locked door, no television, no internet, no way of knowing what’s going on beyond her room. Years pass. Harvey visits now and then, telling her the country has descended into anarchy. They have sex.

This is a book that starts out as a spy thriller and then becomes something very different: a psychological game, a cruel seduction. It’s intriguing and filled with surprises, but for it to work Maggie needs to be, well, a bit thick.