P Company is the week-long pass-or-fail selection within the six-month basic training. It includes a 10-miler, a 20-miler, a steeplechase, a log race, a stretcher race and the trainasium assault course, and you are not allowed to fail or come off any of them. Jay found it very hard at 19.

It is about six months: the hills phase of navigation with big packs in the Welsh mountains, six weeks in the Brunei jungle, surveillance and reconnaissance with observation posts, counter-terrorism, escape and evasion ending in 36 hours of interrogation, and finally parachuting to special forces standard. Around 150 start and 10 to 20 come out of the jungle.

There is 100% humidity and 30 to 40 degree heat while carrying full kit, live ammunition, around seven litres of water and five days of rations. Maps are about 30 years old, so you navigate on ridge lines, and it is fully tactical throughout: even washing or going to the toilet is done in pairs.

Jay jumped with five air troopers as the first stick to mark a drop zone lit by a drone strobe, on a night with zero moon. A stronger wind pushed them past the strobe and they could not penetrate back, landing about a kilometre and a half away. The lesson was that every operator needed more freefall training.

Two years training as a mountain guide in Bavaria showed him a different way of life and his first taste of real freedom. The job had become monotonous, the longer you stay the more you end up behind a desk, and he felt that leaving at 34 still gave him time to build something outside.