Friction among the recruits explodes as leadership is put to the test in a brutal Navy SEAL surf battle and a grueling team waterfall climb.

In a heart-stopping abduction scenario, recruits must escape from the trunk of a moving car, bringing out reckless behaviour in some.

Recruits are chased overland in near freezing temperatures. Once captured, they face intense interrogation before they attempt the final phase of the course, a series of brutal physical tasks called The Sickener, designed to push them over the edge. Who will prove worthy of passing SAS selection?

Recruits face a high adrenalin task as they leap from a moving zodiac into a moving helicopter. Pepper spray conditioning pushes some over the edge. Only with the right mindset will they succeed.

A rare morning of good morale is destroyed by a worrying accident before a high-pressure tactical driving task.

Recruits take part in an extreme tug of war. Facing off against each other, the loser will be dragged off a 100 metre cliff. An assault course will leave them bruised and battered.

The nine remaining recruits learn the hard way about drone warfare. A mountain rappel almost ends in disaster.

The final four must combine all the skills they've learnt to a three-phase final mission, to pass the course, and make selection.

The 13 remaining celebrities face a day of extreme training that claims two voluntary withdrawals and one medical withdrawal.

Armed with rifles, recruits are tasked with a hostage rescue mission, before taking on their most dangerous task yet in near freezing water.

Fourteen everyday Aussies begin the first day of a brutal one week version of the SAS selection course. Only the toughest will survive Hell Week.

The recruits must fight icy waters and make a brutal climb, then attempt a gruelling task over rocky terrain. But with growing fatigue, recruits turn against each other in a bid to survive.

The celebrity recruits must use courage while facing a terrifying balancing act, 30m above ground. Back at base, they face claustrophobia by negotiating a narrow underground tunnel.

A night beasting claims another withdrawal. The recruits come under attack and capture before being facing each other in hand-to-hand combat.

Just five recruits remain as they're sniper skills put to the test.

An aggressive game of murderball pushes the recruits to their limits before a shock VW and a backbreaking grunt task resulting in an unlikely hero.

Entering a dark tunnel filled with obstacles and water, recruits must remain adaptable and battle claustrophobia. Tensions boil over as the recruits attempt to work together.

Recruits are brutally awoken by the sound of gunfire and a botched rescue attempt unfolds. Messages from home test the recruits' emotional resolve while a relentless pack march takes its toll.

Eighteen celebrity recruits undertake physical and psychological tasks to strip them of their egos. On arrival, the recruits face tear gas exposure and interrogation by the ex-special forces' instructors.

Seventeen celebrity recruits have the guts to sign up for the most brutal Special Forces selection course. Their first initiation is to be set on fire, and then survive a plane crash simulation.