Nightsleeper

Joe, an off-duty police officer travelling on the Glasgow sleeper to London, discovers that someone is attempting to gain control and drive the train remotely. He calls Abby, acting technical director of the National Cyber Security Centre, for help. With the entire UK rail network soon under attack, the pair realise, if they fail to get the passengers off in time, their lives may be at risk.

As Abby attempts to bring the train to a halt, the remaining passengers turn on Joe.

When they realise that one of the passengers may be armed and operating in league with the hackers, Joe desperately tries to work out who he can trust. Abby decides to turn the tables on the driver by making a last-minute decision to take the train off the mainline. As Joe closes in on the enemy within and Abby manages to catch the sleeper in her trap, will the police be able to get there in time?

With the passengers turning on each other in the aftermath of tragedy, Abby desperately attempts to rally the traumatised Joe and persuade him to take back control. But when Hud's shock attempt to stop the train his way puts everyone on board in more peril than ever, Joe is suddenly left fighting fires on multiple fronts.

As Hud and Miller interrogate Abby about her past, Saj realises that this is his shot at the big time and decides to try to stop the train his way. Joe, meanwhile, must deal with the deadly aftermath of the shooting whilst working out whether to follow Saj's orders or put his faith in his punch-drunk fellow passengers instead. Could retired train driver Fraser's audacious plan really work?

As dawn breaks and Abby realises the truth, Joe and the others reach the end of the line.