Pratt & McClain's biggest hit single was the theme from the long-running ABC-TV series Happy Days. San Antonio,TX, native Truett Pratt started out singing in the church choir, then joined a rock band in high school. Pasadena, CA, indigene Jerry McClain also sang in the choir. Around the mid-'60s, McClain met Michael Omartian. They formed American Scene and recorded for Dot Records. In 1970, Omartian began a successful record producing career that came to include hits from Christopher Cross, Cher, Dion, Tom Johnston, Jermaine Jackson, Rod Stewart, Donna Summer, and Dionne Warwick ("Love at First Sight," "Deja Vu," "Don't You Ever Take Your Love Away"). He introduced McClain to Pratt. They started a group called Brother Love and began recording commercial jingles.
Becoming Pratt & McClain, they got a deal with ABC/Dunhill Records, recording one album. Later signed to Warner Bros. subsidiary Reprise through producers Omartian and Steve Barri, they were picked to record the theme song to the wildly successful Happy Days. The song was written by Charles Fox and Norman Gimbel, who wrote the themes for other ABC-TV hit shows: Love American Style, Wonder Woman, Laverne and Shirley, and The Love Boat. The original theme song for Happy Days was Bill Haley and the Comets' "Rock Around the Clock." "Happy Days" b/w "Cruisin' With the Fonz" went to number five pop in spring 1976 and was included on the second LP, Pratt & McClain Featuring Happy Days. The follow-up, a cover of Mitch Ryder's "Devil With the Blue Dress On," peaked at number 71 pop in summer 1976. Though the duo never charted again, their lone hit single can be heard during the TV show's opening and closing credits as it runs in perpetual rerun syndication and as a part of cable channel Nickelodeon's Nick at Nite programming. Pratt & McClain's "Happy Days" is available on the Rhino CDs Super Hits of the '70s: Have a Nice Day, Vol. 18 and Have a Nice Decade: The 70s Pop Culture Box.