The first major role Ethan Suplee landed was as the frustrated Magic Eye viewer Willam in Mallrats, directed by Kevin Smith, alongside future My Name is Earl costar Jason Lee. He also appeared briefly in the independent Kevin Smith View-Askew produced Drawing Flies. Smith cast both Suplee and Lee again in later films Chasing Amy and Dogma. They both make cameos in Clerks II.
At the same time as the filming of Mallrats, Suplee also had a recurring role as Frankie “The Enforcer” Stechino in Boy Meets World, from 1994 to 1998.
Suplee’s dramatic performances include the roles of the ruthless white power skinhead Seth in American History X, Vulgar, Ashton Kutcher‘s goth college roommate “Thumper” in The Butterfly Effect, American football player Louie Lastik in Remember the Titans, Johnny Depp‘s buddy and initial drug-dealing partner Tuna in Blow, and the simpleminded Pangle in Cold Mountain.
In 2014, he was cast in the TV Land original sitcom Jennifer Falls, which reunited him with My Name Is Earl co-star, Jaime Pressly.