He first appeared in the show's second episode "The New Jerry", in which he kidnapped Jerry and replaced him to use WOOHP for his plot. Sam also developed a strong crush on him before she discovered he was evil.
In "Mommies Dearest" he attempts to get revenge on the girls by mind controlling their mothers and using them to kill the girls. In "Morphing is so 1987" Tim attempts to destroy WOOHP using "liquid-metal" robots capable of mimicking the appearance of others.
He reappeared in season 4 and became a member of L.A.M.O.S.
Tim Scam is highly intelligent, manipulative, and perspicacious. He originally developed a heat-ray capable of evaporating the Earth's oceans while working for WOOHP. He will likely remain a persistent nuisance to Jerry and the spies. Unlike the show's other villains, who are usually "themed" bad guys whose personalities typically center around a single bizarre personality disorder or childhood trauma, Scam comes across as completely sane (albeit sociopathic). Also, unlike the other villains, whose plans generally involve indulging in their twisted obsessions (which often involve brainwashing people), Scam's plans are centered around all-evil deeds to accomplish his acrimonious and malevolent objectives. Scam kills for killing's sake.