Detective James Knight is in this final, tense chapter of the trilogy. Knight's last-minute assignment to the Independence day shift turns into a race to stop an unbalanced ambulance EMT from imperiling the city's festivities. The misguided vigilante, playing a cop with a stolen gun and uniform, has a bank vault full of reasons to put on his own fireworks show'one that will strike dangerously close to Knight's home.

"You feeling it? We have to get this guy" 4 years after the events of Garibong district round-up operation, Geumcheon Police's Major Crimes Unit is given a mission to repatriate a fugitive who fled to Vietnam. Beast cop Ma Seok-do and Capt. Jeon Il-man intuitively realizes there's something wrong with the suspect's willingness to turn himself in and uncover crimes committed by a terrifying killer named Kang Hae-sang. Ma and his unit begin their investigation...

William Easton is an oily executive who denies John Kramer (a.ka. Jigsaw) access to an experimental cancer treatment. This lands William and a handful of additional lost souls into yet another chamber of horrors. Now, the game is overseen by Jigsaw's acolyte, Detective Hoffman. However, when the FBI draws closer to Hoffman, he is forced to set his game into motion, and Jigsaw's grand scheme is finally understood.

When members of his undercover narcotics team start turning up dead, a Detroit detective teams up with a cocky, young homicide detective to solve the killings, but they soon begin to uncover corruption.