Captain Crook was the McDonaldland character associated with stealing Filet-O-Fish sandwiches.
He was designed as a pirate-themed character, matching the seafood connection of the Filet-O-Fish product. His role gave McDonald's advertising another comic antagonist while also reinforcing the identity of a specific menu item.
Captain Crook is frequently confused with the Hamburglar because both were mischievous villains in the same fictional advertising setting. The distinction is simple: the Hamburglar pursued hamburgers, while Captain Crook was linked to Filet-O-Fish sandwiches.
McDonaldland characters helped McDonald's turn menu items and restaurant imagery into a connected cast. Captain Crook was less prominent in later campaigns than Ronald McDonald, but he remains part of the brand's classic character history.