When Garry Marshall's "Happy Days" premiered on ABC in 1974, the sitcom caught a ride on a wave of Baby Boomer nostalgia generated by George Lucas' "American Graffiti" the previous year. That film was like a time machine for this generation, and they wanted to keep going back over and over again. Alas, this being the pre-vcr and pre-cable age, if they were looking to take that nostalgia trip at home, they were going to be waiting a couple of years for its network television premiere. So Marshall's series, which looked and sounded a good deal like "American Graffiti," was a more than suitable substitute.

Aside from sharing its theme song (Bill Haley and His Comets' "Rock Around the Clock") with Lucas' film, "Happy Days" also cast one of the stars of "American Graffiti," Ron Howard, as its protagonist. Unlike most of the show's young cast, Howard wasn't some...