Original: Bobby Darin ( born Walden Robert Cassotto , May 14 , 1936 -- December 20 , 1973 ) was one of the most popular American big band performers and rock and roll teen idols of the late 1950s and early 1960s .
Simplified: Walden Robert Cassotto ( May 14 , 1936 -- December 20 , 1973 ) , better known as Bobby Darin , was an American pop singer , most famous during the 1950s .