Zero is a ghostly dog that appears to be made of a white sheet, much like a stereotypical ghost. Like Pluto, he has basset hound-esque floppy ears. His "eyes" are just empty holes in the sheet. Zero's snout is very long and thin, and his upper jaw curls upward at the tip. His nose is a small glowing jack-o-lantern like Rudolph's red nose, and his collar is a faded brown color.
Zero first appeared in the 1993 movie The Nightmare Before Christmas. In the movie, Jack finds the door to Christmas Town while he is taking Zero for a walk. Later, when Jack wants to take off through the thick fog to deliver presents, Zero has to light the way. At the end of the movie, Jack and Sally kiss each other as Zero looks at them. He then flies into the air and transforms into a star.
The Nightmare Before Christmas: Oogie's Revenge
Zero can be called upon by Jack when the enemy is hard to defeat. Zero's only known powers are growling and biting.
Zero is a relatively minor character in the Kingdom Hearts series, usually only seen in the background of Kingdom Hearts and Kingdom Hearts II. He is given a slightly larger role in Kingdom Hearts 358/2 Days, where he can sense Heartless and uses this ability to help Jack Skellington and Roxas.
Zero appears in the Haunted Mansion Holiday attraction in the Endless Hallway and the Graveyard scene with Jack. He also appears in Disneyland's Halloween Screams fireworks show, floating over the castle in a similar fashion to Tinker Bell.
- Zero's "Corpse Bride" counterpart is Victor's skeleton dog: Scraps.
- Even to this very day, it is currently unknown who provides Zero's vocal effects in the original film, though many believe it was done by Bill Farmer, Frank Welker, or sound effects from a computer, though there's no evidence support these beliefs.
- Zero makes an appearance in one of Bleedman's webcomic: Grim Tales Down Below. Zero becomes good friends with Grim Jr.