Sung by two different acts, what song was the UK's best-selling song in 1990 and 1995?

"Unchained Melody" is a 1955 song with music by Alex North and lyrics by Hy Zaret. North used the music as a theme for the little-known prison film Unchained (1955), hence the song title. Todd Duncan sang the vocals for the film soundtrack. It has since become a standard and one of the most recorded songs of the 20th century, most notably by the Righteous Brothers. According to the song's publishing administrator, over 1,500 recordings of "Unchained Melody" have been made by more than 670 artists, in multiple languages.

The best-known version of "Unchained Melody" was recorded by the duo The Righteous Brothers for Philles Records in 1965. The song reappeared on the Billboard charts in 1990 after The Righteous Brothers' recording was used in the box office blockbuster film Ghost. This re-released song reached number 1 in the UK where it stayed for four weeks, becoming the UK's top selling single of 1990.

The version by Robson & Jerome is notable as the best-selling single of 1995 in the UK. It also launched the singing career of Robson & Jerome, and became the biggest hit in the UK for Simon Cowell, marking his beginning as an important figure in the music industry.