McCann was born to Irish-American parents in Boston, USA, who came to Lovia in the mid 1930s. He began his acting career in the 1950s with a minor role in El Matador. With the success of The Spy at the box office, he was hired to play Bulletman and became a mainstream actor. In 1967 he married actress Andrea Graves and had one daughter, Elizabeth McCann (1967), who herself is an actress.