Bobby Darin appeared on What's My Line? on January 31, 1965. He was introduced as the Heart Ambassador for the Heart Fund by fellow panelist, Arlene Francis. Hosted by John Daly, What's My Line? was one of the longest running panel game shows in television history. Bobby filled the guest panelist spot very well with the other regular players, Arlene, Dorothy Kilgallen and Bennett Cerf.