Muttley first appeared in 1968 as the snickering canine sidekick to Dick Dastardly in Hanna-Barbera's Wacky Races, voiced by Don Messick, and later starred alongside him in Dastardly and Muttley in Their Flying Machines. His wheezy laugh became his trademark, signalling that a scheme was either underway or had just gone wrong. Decades of television reruns kept the character familiar, and short clips of the laugh later spread through memes, reaction videos and edits, where it still works as instant shorthand for sly, villainous amusement.