A Night at the Opera is the fourth studio album by the British rock band Queen, released on 21 November 1975 by EMI Records in the United Kingdom and by Elektra Records in the United States. Produced by Roy Thomas Baker and Queen, it was reportedly the most expensive album ever recorded at the time of its release. The album’s title is taken from the Marx Brothers film of the same name. They employed a complex production that extensively used multitrack recording, and the songs incorporated a wide range of styles, such as ballads, music hall, dixieland, hard rock and progressive rock influences. Aside from their usual equipment, Queen also utilised a diverse range of instruments such as a double bass, harp, ukulele and more. It also produced the band’s most successful single in the UK, “Bohemian Rhapsody”, which became their first UK number one.