Start Planning Your 12-Day Simpsons Marathon FXX airing all 552 episodes in consecutive order By Newser Editors and Wire Services Posted Apr 10, 2014 11:38 AM CDT 12 comments Comments This undated publicity photo released by Fox shows characters from the animated series "The Simpsons." (AP Photo/Fox, File) (Newser) – The FXX network plans a marathon telecast this summer of Simpsons episodes—all 552 of them, consecutively. The network said yesterday the marathon will start Aug. 21 and continue into Labor Day. FXX programming chief Chuck Saftler said it coincides with the network's purchase of rerun rights and the development of an app that gives access to every episode of the long-running animated series. This fall, FXX will show four hours of episodes every Sunday, up until the time a new episode is aired in prime time on Fox.