Billy is a puppet that has appeared in the Saw franchise. It was used by John Kramer to communicate with his test subjects by delivering recorded messages, often appearing on a television screen or occasionally in person to describe the details of the traps and the means by which the test subjects could survive.



In the film series, before becoming the Jigsaw Killer, John created Billy to be given as a toy to his unborn child. However, Jill, his wife, is shown to miscarry after being hit in the stomach by a swinging hospital door due to Cecil ramming it open without looking. John's unresolved anger was likely a primary motive for creating the puppet as a vehicle for his instructions to trap victims. The traps he created can be seen as a manifestation of his anger with people who he feels do not appreciate having their life, when his unborn baby was killed before having a life of its own.



Although it has never actually been identified in the films, "Billy" is the name by which it is referred by writers, directors, and members of the cast and crew on documentaries and interviews. The name was given to it by Australian creator James Wan, who is the director and co-writer of Saw. Some claim that the name is spelled "Billie", though Wan himself spells it "Billy".



The endurance and popularity of the Saw franchise has resulted in the production of Billy merchandise, as well as references in other media.