The extraordinary untold story of the heroism and sacrifice of the NYPD’s elite rescue squad - the Emergency Service Unit - on 9/11. New York City’s Emergency Service Unit (ESU) is a unique institution in law enforcement; not only is it the busiest Special Weapons and Tactics (SWAT) team in America, the ESU is also one of the top urban rescue units in the world. Indeed it is often said when New Yorkers are in trouble they call the NYPD, and when the NYPD is in trouble they call the ESU. The vital role played by the ESU on 9/11 has long been overlooked, but now for the first time - using previously unseen archive material and moving first-hand testimony – we tell the truly inspirational story of the 9/11 rescue cops.