Ben 10 began as an American animated series on Cartoon Network in 2005, following ten-year-old Ben Tennyson, who discovers a watch-like device called the Omnitrix that lets him change into different alien heroes. The show grew into a long-running franchise with sequels, toys and games, and its theme music became shorthand for childhood Saturday-morning cartoons. Clips of the opening now circulate widely in memes and edits because the tune is instantly recognisable, even to viewers who remember only the hero transformations and the Omnitrix itself.