"So Cruel" is a song by rock band U2. It is the sixth track on their 1991 album Achtung Baby, concluding side one of the album. The song was written at Elsinore in Dalkey. While audio engineer Flood changed reels to listen to a demo of another song, lead singer Bono began to improvise a song on guitar. The rest of the band quickly joined in, creating the first take of the song. It was developed as an acoustic track, with Flood adding overdubs and additional elements later. Bassist Adam Clayton and Flood noted that the technology in the studio was crucial in transforming the acoustic song into the final mix. During the recording sessions for Achtung Baby, guitarist the Edge separated from his wife, Aislinn O'Sullivan. The separation had a major effect on the development of the song, as Bono channelled their pain into the lyrics. Bono said "there were lots of other things going on internally within the band and outside it, and I was working through all of that", noting that the Edge's separation from Aislinn was just one component of that. Thematically the song is about unrequited love, jealousy, obsession, and possessiveness. U2 have performed "So Cruel" live just four times, all of which were on the Zoo TV Tour in 1992. The track was favourably received by critics. Writing and inspiration "So Cruel" was developed by lead singer Bono. Following the recording sessions at Hansa Studios in West Berlin in 1990, U2 resumed the album's sessions in February 1991 at the seaside manor Elsinore in Dalkey, renting the house for £10,000 per month. Producer Daniel Lanois' strategy was to record in houses, mansions, or castles, as he believed it brought atmosphere to the recordings. During the recording at Elsinore, while working on another song, audio engineer Flood changed the reel to listen to an earlier take. Bono picked up a guitar and began to sing. The rest of the band quickly joined in. Flood said, "All of a sudden, almost in the time it had taken for me to wind off the reel and wind the next reel on, it was quite obvious that there was a song about to pop out, and if I wasn't suddenly taking the reel off and getting a new piece of tape on, and changing from monitoring a backing track downstairs to everybody's in the control room wanting to