Only You was originally a hit for Yazoo in 1982. It should have been a hit for Depeche Mode originally, as keyboardist Vince Clarke wrote it when he was in the band, but he ended up leaving Depeche Mode after one album and three hit singles, all of which he wrote, and formed Yazoo with Alison Moyet in 1981, and they had the hit with it the following year. Yazoo only lasted until 1983, and Vince Clarke went on to found Erasure with singer Andy Bell in 1985.
The a capella group The Flying Pickets had a surprise hit with their cover of Only You in 1983.