As training progresses, exercises start to imitate life at war and the nature of the job begins to worry some recruits. And new boss Captain Simon Smith is feeling under pressure.

As the reality of what he may ultimately be required to do as a Marine dawns on Seda from Egypt, he faces a tough decision about whether he should be a Marine after all

The troop face Lympstone's ultimate challenge: the famous Commando Tests. They're all desperate to finish the course together but not all of them will make it through.