Candice Warner

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.

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

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.

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 startled from their sleep by the sound of gunfire, and a fumbled rescue attempt unfolds. The emotional resolve of the group is put to the test with messages from home. A relentless pack march exacts its toll.

Recruits confront their fears head on with a 60m high forward abseil; a rough game of murderball on a black mud plain leaves a recruit with a near concussion.