Sabrina Frederick

The fatigued recruits are dropped from a helicopter into four-degree water while carrying 20kg backpacks. They must make their way to the shore as a group, before racing to the top of a mountain.

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 gruelling SAS selection course.

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

The recruits are armed with rifles to take on a hostage rescue mission, before embarking on a perilous task in near freezing water.

The recruits must crawl across a jagged ravine on one rope above the ocean; the contestants get submerged in cold surf; the recruits experience a physical drilling that puts them on the brink of physical collapse.

Recruits must race up a snow-covered mountain dragging a 60kg sled; a swim under ice in hypothermic conditions will see the weakest of them sent home.