The recruits face their final and toughest challenge: a 12-hour interrogation. Only the strongest survive.

The emotional strain is cranked as the escape and evasion challenge leads the celebs into the darkness as they try to navigate the unknown.

High-wire terror, tough combat and emotional death letters provide a stern test of recruits' composure as the selection process intensifies.

A failed rescue mission, a brutal task and rising pressure test group bonds as armbands are stripped and emotions laid bare.

A brutal race up 27 flights to the top of a dam pushes the recruits hard, after which they must rappel 45 metres back down the dam before free-falling into turbulent water. They must then swim 40 metres to safety in under three minutes. Back at base, nerves shatter and more recruits exit. A high-stakes rescue in a war-torn village tests the remainder's moral courage.

The remaining recruits are hurled into a terrifying escape drill with a single ladder suspended 15 metres up, which must be crossed while under enemy fire. As the heat intensifies, they must trek through a scorching canyon before embarking on an extreme ammo resupply. And the punishing race to a mountain summit with 100kg of kit exposes one recruit's leadership shortcomings.

Phase two begins with chief instructor Billy determined to understand his celebrity recruits inside out. With psychological insight from Dr Gareth and a rare glimpse into Billy's own past, the recruits quickly learn what's expected of them. They're thrown into a life-or-death combat scenario as they're forced to decide in a heartbeat whether to fire or hold their nerve. Then a terrifying 230-metre crawl through mud-filled tunnels pushes fears to breaking point. A brutal beasting follows - and one recruit hands back their armband.

Fourteen British and Australian celebrities - including TV personality Dani Dyer, Neighbours actor Ryan Moloney and rugby world cup winner Ben Cohen - face the most punishing challenge of their lives. In the brutal heat of North Africa, these famous faces are embarking on a savage, condensed version of SAS selection that even they won't be able to charm, spin or tweet their way out of. As the celebrities are stripped of their identities, luxuries and excuses, the brutal physical and mental course - led by Directing Staff Billy Bilingham, Foxy, Rudy Reyes and Chris Oliver - will lay them bare. They'll have no PR teams, filters or followers to rescue them. Instead, they'll face sweat, physical endurance, sand, tears and the truth they've been avoiding. The UK and Aussie recruits are put under extreme pressure as every mistake is punished, every crack exploited, every weakness dragged into the open. Bonds snap, egos shatter, and recruits are pushed so far past their limits they forget they ever had any. And when the dust settles, one question remains: will any of these celebrities make it to the end and impress the DS enough to pass the course? The celebrities begin by facing an underwater emergency escape task before taking on a bout of hand-to-hand combat.