Flex is Kings Poster Flex is Kings Amazon » eBay » The film "Flex is Kings" is a 80 minute documentary from 2013.. Flex is Kings Details Title: Flex is KingsYear: 2013Genres: DocumentaryDuration: 1h 20m Rate this title Have you seen Flex is Kings? Rate it between 1 to 10 below. Log in to your account if you want to rate this title.