Add Yahoo as a preferred source to see more of our stories on Google. A 1974 Happy Days episode was named the “greatest” of the series, but it also led to one of the greatest mysteries in TV history.

CNN — Actor Gavan O'Herlihy, best known for his brief role as the eldest Cunningham son on the sitcom "Happy Days," has died at the age of 70, his agent said. "He was a wonderful actor with a long and ...