Batman: The Long Halloween, Part One, is based on the DC Comics storyline of the same name – a 13-issue limited series written by Jeph Loeb with art by Tim Sale, published in 1996 and 1997.

Directed by Chris Palmer, Batman: The Long Halloween, Part One, is the animated superhero film produced by Warner Bros. Animation and DC Entertainment – the forty-second film in the DC Universe Animated Original Movies line.

During the holidays, a brutal series of murders strike fear into the city of Gotham. Batman sets out to pursue the serial killer with the support of police officer James Gordon and district attorney Harvey Dent.