While honoring Jonah Hill at 2018's Wall Street Journal Magazine Innovator Awards, Channing Tatum recalled the first conversations that he and Hill had about making "21 Jump Street" (via Page Six). According to Tatum, it was Hill's idea, and he even called him up saying that he had a "terrible idea" for a movie. Hill then pitched it, only for Tatum to agree that it was terrible — which was exactly why he was in. Obviously, it worked out and "21 Jump Street" was, and still is, a huge success, but Tatum also revealed the one condition he had for Hill in order for him to commit to the project.
Tatum explained, "I did only have one condition on doing '21 Jump Street.' I had never done a comedy before, and naturally was terrified ... and I guess people laughed at my movies but probably not intentionally. So I made Jonah promise me that he was going to make me funny, and he promised. So I consider myself one of the first people that he's directed as Jonah Hill the director."
Tatum's comment about being one of the first people that Hill has directed is in reference to 2018's "Mid90s," the award-winning film that served as Hill's directorial debut, which came out around the same time as the Wall Street Journal Magazine event (via IMDb). Although Tatum has not officially been directed under Hill (yet), "21 Jump Street" certainly benefited from Hill helping Tatum with the humor.