"Invisible" is a song by Irish boy band D-Side, released as the third single (second in the United Kingdom[1]) from their first studio album, Stronger Together (2003).

The same year, American Idol second two runner-up Clay Aiken covered the song and reached number 37 on the US Billboard Hot 100 with his rendition.

The song has been frequently targeted by music critics for its unsettling lyrical content, with several calling the track a "stalkers' anthem".

[2] Can't Stop the Pop called it a "meticulously crafted" track, praising its composition, the band's vocals, and its airplay appeal, but criticised the lyrical content for being too "creepy", noting that the chorus has aged poorly.

[1] Commercially, "Invisible" became the group's third consecutive top-10 hit in their home country, debuting and peaking at number five on the Irish Singles Chart on 17 July.

[1] Released two months after D-Side's version, Aiken's cover charted within the top 40 of the US Billboard Hot 100, peaking at number 37 in January 2004.

After recording the rest of the demo in Minneapolis, Aiken and his coworkers discovered that D-Side had released their version, so they discussed whether to issue the song in the UK.