“Nightsleeper is a real-time thriller for the BBC, in which an overnight train is taken over by a hacker. Among the 12 passengers trapped on board is troubled policeman Joe Roag.

With the train hurtling towards death and destruction, and all CCTV and communications cut, Joe manages to make contact with director of cyber security Abby Aysgarth, via satellite phone. Abby and her team quickly discover that the entire railway network has been hacked, making the situation impossible to control.

Joe and Abby, two strangers connected only by phone, must find a way to stop the train, save its passengers and identify the mysterious ‘driver’ who has infiltrated the system. But their job is complicated when they find themselves under suspicion, after the security services and the passengers on board uncover secrets from their pasts.”