The animated television series The Grim Adventures of Billy and Mandy premiered on Cartoon Network, marking the beginning of the show's run.
The series released its first TV movie, 'Billy & Mandy's Big Boogey Adventure,' expanding the show's storyline and popularity.
The original run of The Grim Adventures of Billy and Mandy concluded on Cartoon Network after several successful seasons.
Billy and Mandy win a limbo contest against Grim, forcing him to become their best friend and servant.
After losing the limbo contest, Grim reluctantly becomes friends and accompanies Billy and Mandy on their supernatural adventures.
Billy accidentally frees the Boogeyman from his prison, unleashing chaos in Endsville.
Irwin, the nerdy vampire, becomes a recurring character and sometimes ally to Billy and Mandy.
Episodes explore Grim's history before meeting Billy and Mandy, revealing his struggles as the Grim Reaper.
The villain Lord Pain emerges as a major antagonist, threatening Endsville and challenging Grim and friends.
Jack O'Lantern tries multiple times to regain power and defeat Grim, including his various plots involving darkness.
Billy, Mandy, and Grim aid in a battle for control of the Underworld, facing several terrifying foes.
Nergal returns multiple times, initially as an antagonist, but later becomes an occasional friend and ally.
Billy's and Mandy's families encounter supernatural bizarre events, deepening the series' character dynamics.
