In the late 1960s, Barbeau moved to New York City and worked "for the mob" as a go-go Dancer. She made her Broadway debut in the chorus of Fiddler on the Roof, and later took the role of Hodel, Tevye's daughter; Bette Midler played her character's sister. She left Fiddler in 1971 to play the leading role of Cookie Kovac in the off-Broadway nudie musical Stag Movie. Barbeau, as Cookie Kovac, and Brad Sullivan, as Rip Cord, were "quite jolly and deserve to be congratulated on the lack of embarrassment they show when, on occasion, they have to wander around stark naked. They may not be sexy but they certainly keep cheerful," wrote The New York Times theater critic Clive Barnes in an otherwise negative review. Barbeau went on to star in more than 25 musicals and plays, including Women Behind Bars, The Best Little Whorehouse in Texas, and Grease. She received a Theater World Award and a 1972 Tony Award nomination for her portrayal of tough-girl Rizzo in Grease.