Released in 1975, what was the only UK No. 1 single by The Four Seasons?

'December, 1963 (Oh, What a Night)' was the only song performed by The Four Seasons to reach No. 1 on the UK Singles Chart. The single was released in December 1975 and eventually hit number one on 21st February 1976. Originally, the lyrics mentioned 5th December 1933, the date of the repeal of Prohibition, but the band decided to change the year to 1963, in reference to the band member Bob Gaudio's courtship with his wife.

The Four Seasons is an American rock and pop band that became internationally successful in the 1960s and 1970s. During the 1970s, they were also known as Frankie Valli and the Four Seasons. Frankie Valli, the lead singer of the band, is known for his falsetto tones. Songwriter Bob Gaudio (keyboards and tenor vocals), Tommy DeVito (lead guitar and baritone vocals), and Nick Massi (electric bass and bass vocals) were the other founding members of the band.

Although The Four Seasons only had one number one in the UK, they reached the top spot on the 'Billboard Hot 100' in the US on several occasions. Singles include 'Sherry' (1962), 'Big Girls Don't Cry' (1962), 'Walk Like a Man' (1963), and 'Rag Doll' (1964).