Kealy was the commander of a nine-member SAS squad, which came under attack from hundreds of Popular Front for the Liberation of the Occupied Arabian Gulf guerillas during the Dhofar Rebellion in Oman.
Kealy died of hypothermia on 1 February 1979 when he joined SAS candidates on a selection march in the Brecon Beacons in deteriorating weather conditions.
As a direct result of this and similar incidents, those attempting SAS selection are now allowed to carry only useful items in their bergens when marching.
In the novel, Mike Kealy is murdered by a group of contract killers called "The Clinic" in revenge for his role in Oman that had resulted in the killing of a sheik's son.
Rather than succumbing to the extreme weather conditions while on an endurance march, as actually happened, the fictional character dies after going into diabetic shock following him being injected with insulin by "The Clinic".