Retired Detective Inspector Alex Ridley is lured back into service as a consultant detective when his former protégée, Carol Farman, needs help cracking a complex murder case.

A veteran beat cop and teenage girl fall to their deaths from a tower block in south-east London, leaving a five-year-old boy and rookie police officer Lizzie Griffiths on the roof, only for them to go missing. Detective Sergeant Sarah Collins is drafted in to investigate, working to find Lizzie before she comes to serious harm, but also to uncover the truth behind the grisly tower block deaths.

It’s game night for a group of friends, and while the rivalry is light, the dangers are increasing.

Three friends in their late twenties have one last lock-in before one of them moves to Hong Kong; revelations, recriminations and regrets ensue.