[1][8][9] After hearing a concert by the African-American lyric tenor Roland Hayes he gave up his medical education to study singing and music,[1][9] and soon was performing classical works.

[8][9] About this time, he met the Trinidadian band leader Gerald Clark,[3] perhaps the most significant promoter of calypso in New York City.

[1][9] He made his debut as Sir Lancelot in 1940 at New York City's Village Vanguard nightclub.

[11] Sir Lancelot became a regular at the Village Vanguard, and by the 1940s "was widely considered the hottest calypsonian in the city.

[13][14] In the 1940s he returned home for the first time but was largely disowned by his family, which felt that his calypso singing had shamed them.

[3] Sir Lancelot wrote the calypso song "Shame & Scandal" (also known as "Fort Holland") in response.

[8] He composed several popular calypso songs with left-wing lyrics in the 1940s, including "Defenders of Stalingrad" and "Walk in Peace" (1946).

[26] Sir Lancelot spent six years touring in Europe in the 1950s, which negatively impacted his career in the U.S.[9] Sir Lancelot's last film appearance was in 1958 (with Yul Brynner in The Buccaneer),[8] although he made a noted appearance in an episode of The Andy Griffith Show in 1967.