Yoo Young-chul, known as the "Raincoat Killer," terrorized Seoul between 2003 and 2004. Much like the killer in the movie, Yoo targeted victims randomly and used blunt instruments or knives, often attacking people in their homes or in secluded areas. The sheer randomness and brutality of his crimes created a similar atmosphere of "unpredictable evil" that the film captures so effectively. The "Gangster" and "Cop" Dynamic

The movie also touches on a very real frustration within the Korean public at the time: the difficulty of catching "random" killers before the widespread use of CCTV and advanced DNA profiling. By grounding the "Devil" in the traits of real murderers like Yoo Young-chul, the film taps into a genuine historical anxiety. The Hollywood Connection

The story’s "truth-adjacent" grit was so compelling that it caught the attention of American producers. Sylvester Stallone’s production company, Balboa Productions, actually signed on for a Hollywood remake before the original was even out of theaters—with Don Lee (Ma Dong-seok) set to reprise his role as the gangster. Final Verdict