William George Heirens (November 15, 1928 – March 5, 2012) was a convicted American serial killer who confessed to three murders in 1946. Heirens was called the Lipstick Killer after a notorious message scrawled in lipstick at a crime scene. At the time of his death, Heirens was reputedly Chicago's longest-serving prisoner, having spent 65 years in prison.
He spent the later years of his sentence at the Dixon Correctional Center in Dixon, Illinois, (Inmate No. C-06103). Though he remained imprisoned until his death, Heirens had recanted his confession and claimed to be a victim of coercive interrogation and police brutality.
Charles Einstein wrote a novel called The Bloody Spur about Heirens. The novel was later adapted into the film While the City Sleeps by Fritz Lang.
On March 5, 2012, Heirens died at the UIC Medical Center.
The letter and envelope are both handwritten. The letter is signed, Bill Heirens.