Astle had a background in television sitcoms, including Dave's World, Coach, Clueless, and the Saturday morning series Fudge. He also wrote single episodes of the 1980s revival of The Twilight Zone and the 90s revival of The Outer Limits and went on to create the Disney Channel series So Weird. Astle moved from television into movie screenwriting (with writing partner Matt Ember), starting with Failure to Launch and including the film version of Get Smart and the animated features Epic and Home.