Clancy Brothers and Tommy Makem - Treasure Island: Johnny's Gone to Hilo (TV show, 1960) 

The Clancy Brothers and Tommy Makem appeared in the TV adaptation of Robert Louis Stevenson's classic, Treasure Island, along with Boris Karloff, Hugh Griffith, and Michael Gough. The program was broadcast on March 5, 1960 as part of the DuPont Show of the Month on American television.
In this clip, the Clancy Brothers and Tommy Makem sing the sea song, "Johnny's Gone to Hilo," over the closing credits. The group was billed in the credits as The Clancy Boys and Tom Makem. Tom Clancy also got a credit for his part of Israel Hands.
Although Tom Clancy would continue his acting career, this is one of the final acting jobs for Paddy and Liam Clancy and Tommy Makem before they devoted themselves full-time to singing.