Jeremy Garelick just wants to make people laugh. But to sustain an incredibly successful career doing that, he has solved some pretty knotty problems. In his twenties, he didn't know how to write a script but transformed himself from a production assistant into a sought-after screenwriter in just a few years. He would go on to co-write The Hangover.

When movie studios refused to make the kind of comedies he loves, because they thought the return on smaller films wasn't worth their effort, he purchased an old high school as a film set, kept costs low, and arranged his own financing. Today, he controls every aspect of production on a campus called American High.

While Hollywood struggles in the streaming era and sees diminishing returns from old, overused properties, Garelick has figured out his own business model, how to grab  ...