| "Unknown Caller" | |
|---|---|
| Song by U2 | |
| from the album No Line on the Horizon | |
| Released | 27 February 2009 |
| Genre | Rock |
| Length | 6:03 |
| Label | Island |
| Songwriter(s) | U2, Brian Eno, Daniel Lanois |
| Producer(s) | Brian Eno and Daniel Lanois, with additional production by Steve Lillywhite |
"Unknown Caller" is a song by Irish rock band U2 and the fourth track on their 2009 album No Line on the Horizon. It was written from the perspective of a drug addict, who begins to receive bizarre text messages on his cellphone. The song was developed very early during the No Line on the Horizon sessions, and was recorded in a single take.