In a bid to be admitted into the Australian Commando Regiments, a small group of military candidates are now undertaking one of the toughest courses in the Australian Defence Force. They are pitting their bodies against the training requirements and the demands of highly discerning instructors. After 4 initial days of intensive activity and challenges, the grueling commando selection course has reached its most difficult period. Demarcation. An intense 3 to 4 day period, within the selection course, that consist of extreme challenges that will ultimately determine which of these candidates has what it takes to successfully complete the selection course.