Joe Roag (Joe Cole) is coming home to London from Glasgow. When he helps stop a mugging, Joe gains the gratitude of the staff and passengers. In London, Abby Aysgarth (Alexandra Roach), is an overworked cyber security officer about to go on holiday. Until a call comes in, a hack is made and Joe and Abby find themselves having to trust complete strangers to survive…

Of course this is pulpy. Vastly, relentlessly so. If you know anything about computers, cyber security or trains you’re either going to be deeply annoyed at points or sincerely charmed. If you write, then you’ll either be annoyed by the choices that get made or impressed that Laura Grace and Nick Weather mined every possible detail of their glorious premise. Every train action beat you’re imagining? Happens. Every hacker twist you’re imagining? Happens.

But what makes this work is that they aren’t the only things that happen. There’s a great mid season twist which jinks the show one way and then slams it another, and the back half especially is excellent at depicting the sort of frantic storm of indecision and information that crises are swept up in. The show is still so pulpy that the ending involves a last minute onsite hack and a speeding train but it never pretends to be anything else. Honestly, it revels in its pulpy roots. Honestly, it should.

Because Nightsleeper has cracked the case of how to do pulp right in 2024: make it about people. The cast are uniformly very strong with James Cosmo, Ruth Madeley and Sharon Rooney standouts as they always are in anything they do. But what powers the show is the intensely likeable, grounded, human leads. Joe Cole, best known in these parts as the living embodiment of murder in Gangs of London, is a deeply charming everyman lead. He’s John McClane without the attitude, Jack Bauer with the capacity to feel humour and pleasure. He’s also doing his best in impossible situations and the show never lets us forget that. Facing a difficult situation, he mutters ‘Oh no’, to himself. His first response, in that first incident, is complex and subtle and a surprising amount of the show spins out of it.

But the breakout star here is Alexandra Roach. Abby is a complex woman with a wickedly sharp deductive mind, principles wider than her job, and abject terror at what’s happening. That last is absolutely key, as the incident on the train spreads and she and Joe talk not just to keep each other informed but to share the load. No one is okay. No one is alone. Everyone is trying their best and Roach’s determined, empathetic and cheerfully grumpy spook is a delight to watch navigate the storm that starts on the train.

Verdict: Nightsleeper is going to annoy you if you can’t suspend disbelief. Suspend disbelief. Embrace the ride and you’ll find under the pulpy action there’s a character study full of deeply flawed, deeply likable people doing their best. 8/10

Alasdair Stuart