In October 1932 Sargent suffered a near-fatal attack of tuberculosis. For almost two years he was unable to work, and it was only later in the 1930s that he returned to the concert scene. In 1936 he conducted his first opera at Covent Garden, Gustave Charpentier's "Louise". He did not conduct opera there again until 1954, with Walton's "Troilus and Cressida", although he did conduct the incidental music for a dramatisation of "The Pilgrim's Progress" given at the Royal Opera House in 1948.