The Smiley face murder theory (variations include Smiley face murders, Smiley face killings, Smiley face gang, and others) is a theory believed by retired New York City detectives Kevin Gannon and Anthony Duarte. They say that a number of young men found dead in bodies of water across several Midwestern American states from the late 1990s to the 2010s did not accidentally drown. They believe that they were victims of a serial killer or killers.