It’s a bit Danny Boyle, a bit Guy Ritchie, and a lot more harrowing than anyone would expect who tunes in to a show called Stags, starring Charlie Cooper from the bittersweet comedy This Country. Daniel Cullen’s six-part drama takes a group of friends, sends them on a debauched week in an unnamed South American country to celebrate the impending wedding of one of their own, then locks them in a godforsaken island prison run by two feuding siblings and leaves them fighting for survival.

Stu (Nico Mirallegro) is the bachelor and Ryan (Corin Silva) and Ant (Cooper) are his best friends. They’re the kind of friends who will come and help you find the £5,000 engagement ring you buried on a pebble beach as part of your marriage proposal, without really thinking about the logistics. Whether they’ll also be the kind of friends who can stop you being tortured in prison is one of the questions – perhaps the most pressing – that angrily plagues Stags.

The rest of the stag party group consists of Stu’s university friends Hugo (Paul Forman) and Clem (Sophie Lenglinger), his fiancée’s father John and his brother Kai (Cavan Clerkin and Jojo Macari), and Greg (Asim Chaudhry), whose connection to Stu is not entirely clear. Kai buys the drugs for the week-long party, Ryan gets the leftovers through airport security when it’s time to go home, and Greg collapses when one of the balloons full of coke he swallowed bursts in his stomach while they wait. This is why they are thrown in jail.

From there, it descends into chaos – which Cullen expertly keeps under control for us, but oh god, those poor idiots (and John). Clem disappears before they arrive, her fate unknown, although the guys do note that there are women in the prison. John and Kai – as Kai is the only one who speaks Spanish – set out to find the prison warden and get him to contact the British embassy. The warden meets with them via video call and assures them that the embassy will immediately step in to free a group of British idiots caught smuggling drugs. When a message arrives from the consulate saying they are aware of the case and will likely spend five or six years in custody, their abandonment feels complete.

A reluctant Hugo is left to care for Greg, now also wounded by a gunshot that I honestly missed in all the excitement of their collective arrest. Stu, Ant, and a reluctant Ryan make their way through the sprawling prison, which features a classroom full of children, as they search for a doctor. They eventually find one, but it goes even less well than you might hope – although Cullen has ratcheted up the tension and fear so expertly by this point that it’s almost a relief when the first bit of blood comes.

As the first blood is drawn, Hugo and Greg are approached by two groups of children with Google Translate on their phones. They are emissaries of the brother and sister who run the store, demanding to know how much money they want to borrow at an impossible interest rate to secure medical services for Greg, and from whom. Greg chooses his sister Selma (Paulina Gálvez). They are invited to dinner in her beautiful garden, where they learn that he told her Greggs was his family’s, and she learns that it is not, leaving his friends to pay for his $200,000 medical bill.

One final twist later, we’re done with the opening episode (the only one available for review). It’s a thrilling journey, superbly filmed, wonderfully acted by all, and peppered with numerous conflicts – between classes, between temperaments, between loyalties, and between collective and individual responsibility – and it’s built on a premise that’s not too far-fetched to keep the stakes from feeling real and high. You care about these idiots – more than the British Embassy, ​​at least.