He greatly resembles his cousin Cookie, but since the two don't share the screen at first, Luis believes that Apple Monster is merely Cookie in disguise. He assumes this is part of some scheme to trick him and others out of cookies, but finds that Apple Monster has no taste for cookies, rather wishing to chow down on apples. He takes an apple from Luis, one from David, and the whole supply of Mr. Macintosh's fruit cart.
Luis and David try to reveal his true identity by tempting him with a box of cookies, which instead baits the real Cookie Monster. The two cousins share a nice reunion.
The puppet is repurposed from the Cookie Monster puppet used during the second season.