Noël Coward had little formal music training, even relying on assistants to notate and score his music. However, his facility with words and pleasing melodies made him one of the most loved playwrights and writers of musical comedies of the twentieth century. Today best-remembered for light, sophisticated comedies, he also wrote deliberately provocative social commentary. Coward showed early performing talent and made his professional debut in 1911, launching a successful acting career, particularly after artist Philip Streatfield and socialite Astley Cooper promoted his talent and acted as his social mentors. Too young for military service during the first years of World War I, he continued to act, making his film debut in 1917 in Hearts of the World. Called up in 1918, he never saw combat, but his absence hut his acting career. Although his artistic training solely consisted of a few years at a choir school, a handful of dance lessons, and avid reading, he was confident enough to start new careers as a writer and composer. His first full-length play, I Leave It to You, opened in the West End in 1920. His first trip to the United States was unsuccessful. After merely pleasant reviews for his next play, he decided to gamble for notoriety by writing and appearing in The Vortex, a shocking drama about drugs and sex scandals in the upper classes. A sensation, the play established him as a star; revues and musicals in New York and London included his songs; and his subsequent plays, typically milder in content, met with success. In 1929, he produced his first complete operetta, Bitter Sweet. His next great drama success was the comedy Private Lives in 1930, followed by Cavalcade in 1931. A movie version of Cavalcade won the 1933 Academy Award. A string of successes followed, including his 1932 revue Words and Music and Design for Living (1933), which dealt with the scandalous topic of bisexuality. More operettas and musicals followed. During World War II, he continued to write plays, including Blithe Spirit in 1942. In addition, he entertained troops overseas and wrote, directed, and starred in the war movie In Which We Serve. After the war ended, his popularity faded, as tastes for comedy and drama changed, but he continued to write musicals and plays until the end of his life.