At age 20, Keel was overheard singing by his landlady, Mom Rider, and was encouraged to take vocal lessons. One of his music heroes was the great baritone Lawrence Tibbett. Keel later remarked that learning that his own voice was a "basso cantante" was one of the greatest disappointments of his life. Nevertheless, his first public performance took place in the summer of 1941, when he played the role of Samuel the Prophet in Handel's oratorio "Saul" (singing a duet with bass-baritone George London).