John Wayne Gacy, Jr. was an American serial killer and rapist, also known as the Killer Clown, who was convicted of the sexual assault and murder of a minimum of 33 teenage boys and young men in a series of killings committed between 1972 and 1978 in Chicago, Illinois.

All of Gacy's known murders were committed inside his Norwood Park home; his victims would typically be lured to this address by force or deception and all but one victim was murdered by either asphyxiation or strangulation with a tourniquet (his first victim was stabbed to death). Gacy buried 26 of his victims in the crawl space of his home; three further victims were buried elsewhere on his property, while the bodies of his last four known victims were discarded in the Des Plaines River.

Two page typed letter to 13 yr old pen pal. Letter is general content and is dated December 3, 1989. Letter is signed John in pen and is in good condition, envelope is in fair condition. Included is an original 'They Call HIm Mr. Gacy' book flyer that Gacy included inside the envelope.