"Perfidia" (Spanish for "perfidy", as in faithlessness, treachery or betrayal) is a song written by Alberto Domínguez (1911–1975), a Mexican composer and arranger born in the state of Chiapas, about love and betrayal. Aside from the original Spanish, other renditions exist, including English and instrumental versions. The English lyrics are by Milton Leeds. The song was published in 1939 and became a hit for Xavier Cugat in 1940. Desi Arnaz sings the Spanish version in the 1941 film Father takes a Wife which starred Gloria Swanson. This version was used by director Wong Kar-wai in his films Days of Being Wild, In the Mood for Love, and 2046.