What McDonald's character was used to promote the chain's Filet-O-Fish sandwich?

Captain Crook was the McDonald’s character used to promote the Filet-O-Fish sandwich.

Captain Crook appeared as a pirate-themed member of McDonaldland’s character lineup. His design and nautical identity connected him with fish, making him a natural advertising representative for the Filet-O-Fish rather than for McDonald’s hamburger products.

The character belonged to the same broader fantasy world as Ronald McDonald, Mayor McCheese, Grimace, and the Hamburglar. McDonald’s used these figures to give individual foods and brand ideas memorable personalities, especially in advertising aimed at children.

Captain Crook is sometimes confused with the Hamburglar because both were portrayed as mischievous figures. Their food associations were different: Captain Crook was linked to the fish sandwich, while the Hamburglar was defined by his desire for hamburgers.