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.

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