The 24-hour event will take place at Disneyland and California Adventure parks in Anaheim, as well as the Walt Disney World Resort in Florida, from 6 a.m. on May 23 to 6 a.m. on May 24.
Guests are encouraged to dress up as their favorite Disney hero or villain. Special events centered on good-vs.-evil will be held throughout the night.
The announcement was made in a Tweet that included a photo of 140 Disney characters in a hashtag formation.
Disneyland previously offered 24-hour promotions during Memorial Day weekend last year and on Feb. 29, 2012 to celebrate Leap Year.
