Jack Skellington is the "Pumpkin King" of Halloween Town. He is responsible for coming up with new and exciting ideas for each year's Halloween festivities. He first appeared in Tim Burton's "The Nightmare Before Christmas".

In Kingdom Hearts, Jack takes a liberal role of performing a scary Halloween, in this case, using the Heartless. He asks Dr. Finkelstein to make a heart for the creatures so they can dance, but the Heartless get loose and wreak havoc in Halloween Town. He requests the help of Sora to find a solution. However, they take so long to fight Oogie Boogie, he regretfully has to cancel Halloween for a year due to a lack of material to go on, promising something terrifying next year.Jack in his Santa costume in Kingdom Hearts II, he takes a comparable role to his character in the movie. He tries to take Santa's place (for the second time), and helps save him from a resurrected Oogie. Eventually, thanks to Santa, he realized that it his duty to take care of Halloween, as much as it is for Santa and Christmas. His Santa suit then helps Sora open a new pathway to the Pride Lands.

Later, Jack is blamed for stealing the presents from Santa's factory. He teams up with Sora again to help solve the mystery and clear his name. They do this by hiding in a giant present and tricking the thief into stealing it. Jack and Sora then defeat the thief, who turns out to be Dr. Finkelstein's Experiment, and save Christmas. After that, Santa lets Jack ride in his sleigh. Later, Sally helps him realize that the most important thing of Christmas is not the gift box, nor the present inside it, but the wish of the giver to make someone happy.