The American version was adapted by actor Denis Leary and screenwriter Bob Fisher.

[3] The series follows the workday of three Emergency Medical Technicians with a fictional Chicago private ambulance company, named Eminent, and the unusual situations—often crude or humorous—people in need of their assistance are in.

In June 2011, it was announced that Denis Leary and Bob Fisher were developing an adaptation of the 2011 British comedy-drama Sirens, created by Brian Fillis and inspired by Tom Reynolds's book, Blood, Sweat & Tea about the London Ambulance Service.

However, a deal with Fox Television Studios was carefully being studied over VOD rights.

[6] The network announced that Sirens would premiere in the first quarter of 2014 and would later state that two back-to-back episodes would air together on March 6, 2014, then resume normal programming the following week.