Captain Crook was introduced by McDonald's in 1971 to promote the Filet-O-Fish sandwich.
The pirate-themed character joined the expanding McDonaldland cast during a period when McDonald's used fictional personalities to give individual foods their own advertising associations. Captain Crook's name, costume, and nautical presentation connected him with fish and the Filet-O-Fish rather than with hamburgers.
Captain Crook is commonly confused with the Hamburglar because both were mischievous characters and appeared in the same broader advertising universe. Their product associations were different: the Hamburglar pursued hamburgers, while Captain Crook was tied to the fish sandwich. The distinction matters when identifying historical McDonald's campaigns.
The character was part of McDonald's wider 1970s branding strategy, which used recurring characters, catchphrases, and fantasy settings to make menu promotions memorable. As McDonald's advertising later became less dependent on the full McDonaldland cast, Captain Crook became much less visible than Ronald McDonald and the core Golden Arches identity.