The series follows the Paramedic Program of the Los Angeles County Fire Department with the focus on the personnel of Fire Station 51, in particular Fireman Johnny Gage played by Randolph Mantooth and Fireman Roy DeSoto played by Kevin Tighe. Furthermore, the paramedics coordinated with the staff of Rampart General Hospital with Dr. Kelly Brackett (Robert Fuller) and Dr. Joe Early (Bobby Troup, the bandleader who wrote Route 66) and Chief Nurse Dixie McCall (Julie London).
The show highlighted the adventures of the still fledgling paramedic program and its popularity caused phenomenal growth in emergency care in throughout North America. The show was also credited for demonstrating first aid techniques that enabled some viewers to save lives in real emergencies.