The Journey of Billy and Mandy

is the 2020 animated adventure film based on The Grim Adventures of Billy and Mandy. It was directed by the series creator, Maxwell Atoms who also written it. The film sets in the world where Billy and Mandy are teenagers when they accidentally got transport into the Underworld where they must find a way out before the Boogey Man and Nergel will take over Endsville. The film sets in the same world as Ed, Edd n Eddy the Movie: The Ed-Touchables and serves as a epilogue of the series. It is the second film of the Cartoon Network's Cinematic World.

Story
The animated film follows two teenagers, a boy named Billy, a slow-witted happy-go-lucky boy who dreams to become a cartoonist, and Mandy—his dark and cynical best friend who decided to become an actress, who accidentally got transported into the Underworld where they meet the Grim Reaper. Now, they must team up with Grim Reaper on a grand adventure to get out of the Underworld before the Boogey Man and Nergel will conquer Endsville.

Cast and Characters

 * Richard Steven Horvitz as Billy/Harold, Billy is a happy-go-lucky boy who dreams to be a cartoonist and Harold is Billy's father and Gladys' husband.
 * Grey DeLisle as Mandy, Billy's childhood best friends who decide to be an actress.
 * Greg Eagles as Grim Reaper/Sperg
 * Vanessa Marshall as Irwin
 * Rachael MacFarlane as Mindy
 * Martin Jarvis as Nirgel, one of two main antagonists of the film who plans to keep Billy and Mandy in the Underworld forever.
 * Fred Willard as the Boogey Man, one of two main antagonists of the film who plans to steal Grim's powers to conquer Endsville.