Grimace was originally depicted as a purple milkshake thief.
When Grimace first appeared in McDonald’s advertising in 1971, the character had multiple arms and was described as stealing milkshakes. This early version was more mischievous and unsettling than the friendly, large purple character familiar from later campaigns.
McDonald’s soon simplified Grimace’s design and personality. The character became a good-natured companion to Ronald McDonald and other McDonaldland figures, while the milkshake-stealing concept was dropped. The redesign made Grimace more suitable for children’s advertising and easier to recognize in merchandise and restaurant promotions.
The character’s exact species has never been consistently defined, which has led to many fan theories. Those theories should not obscure the documented branding history: Grimace’s earliest advertising role involved taking milkshakes, while his later identity emphasized friendship and playful participation in the McDonaldland cast.