|Portrayed by||Patrick Fischler|
|First appearance||The Benefactor|
|Final appearance||Six Month Leave|
Jimmy Barrett is a shock-comic. He was hired by Sterling Cooper Advertising Agency to do TV spots for Utz Potato Chips. ("The Benefactor") Later, he gets a deal for a television show, "Grin and Bear It".
Jimmy insults one of the owners of Utz Potato Chips, Edith Schilling, but later apologizes for his behavior, attributing it to his on-screen persona and that he can't help but crack jokes when he comes across the opportune time.
While this is happening, his wife Bobbie Barrett becomes more involved with Don and eventually begins an affair with him. Unbeknownst to Jimmy, she at one point leaves with Don for the beach, but they get into a car accident en route. Don ends their affair after he learns she's been gossiping about him, and Jimmy becomes aware of the situation.