Trivia

The characters Richard Haywood and Justin Pendleton are loosely based on real-life murderers Richard Loeb and Nathan Leopold.

This is the fourth Hollywood film adaptation of the infamous 1924 Leopold-Loeb murder case. The first was Alfred Hitchcock's Rope (1948), the second Richard Fleischer's Compulsion (1959) and the third Tom Kalin's Swoon (1992).

Ryan Gosling threw up as he filmed the murdering scenes.

The title refers to the song "Murder by Numbers," written by Sting and Andy Summers and performed by The Police, about planning the perfect murder.

Ryan Gosling was in a relationship with Sandra Bullock, having met on the set (May 2002-July 2003).