Merrick Watts

Celebrities undertake a series of extreme tasks, including jumping backward out of a helicopter and hand-to-and combat, as they begin the challenge of completing the grueling SAS selection course.

Recruits are pushed to tackle their fears head-on in a 60m high forward abseil; a brutal game of murderball on a black mud plain leaves one recruit with a near concussion.

In an abandoned slaughterhouse, recruits face a life-or-death decision before they are drilled physically into the early hours of the morning.

In a punishing day, recruits crawl across a jagged ravine on a single rope above the ocean, are submerged in crashing, cold surf, and face a physical drilling that leaves them on the brink of collapse.

In freezing waters with plummeting body temperatures, the recruits must wait to be rescued by their teammates; an emotional departure surprises the group.

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.