`999: Rescue Squad' allows for an unprecedented behind-the-scenes perspective of HART, the Yorkshire Ambulance Service's `Hazardous Area Response Team'. HART is one of 15 specialist medical units set up after the 7/7 London bombings to treat badly injured patients in extreme environments. The series captures the banter and the blood, sweat, and tears of a training regime that demands top levels of physical fitness and skills, which allows the team to perform surgical procedures in a range of locations. The footage captured by a drone and body cameras provides a unique perspective on the drama that comes with the day-to-day life of the HART medical unit.