The Grim Adventures of Billy and Mandy (2001)

Season 4: Episode 1

At school, Billy, Mandy, and Irwin look for a club to join. Irwin plans to join the Macrame club to meet girls; Billy inquires on the Junior CIA club, which forcefully recruits him; Mandy joins the "Secret Snake Club", a snake-themed club consisting of three geeks. The nerds reveal that their "secret agenda" is to resurrect Shnissugah, a giant snake which lived hundreds of years ago in Canada, to take revenge against the popular kids, but they lack the power of the Underworld to do so. Mandy calls for Grim, who proceeds to revive Shnissugah through the internet. Billy, as a junior agent of the CIA, stops a criminal plan by Irwin, who was using the Macrame club for personal gain; and Shnissugah turns out to be a tiny, 8-cm (3.14-in) long, harmless snake.