"6 Underground" is a song by the British band Sneaker Pimps on their 1997 album "Becoming X". At first, the song had moderate airplay. However, after being added into the soundtrack of the 1997 movie The Saint, the song became more ubiquituous on radio stations. It was a crossover success, mainly in the rock, alternative, and pop stations. Chartwise, the song peaked at number 2 on the Billboard charts.

The music video of this song gives of a dark atmosphere. Throughout the video, the camera focuses on Kelli Dayton singing in the middle of a dark room sitting on a stool. Occasionally, clips of the other band members are shown. The camera follows Kelli as she slowly walks around the darkened room singing the song. The video ends with a closeup into the expression on Kelli's face.

Lyricwise, the structure of the song is similar to Joan Jett's "I Love Rock N' Roll". Near the end of the song, it goes into what seems to be the beginning the chorus but turns out to be another verse. Most reviewers state that this pseudoending tease gives the song a more meaningful tie to the themes in "The Saint". Similarly, the two most quoted lines of the song: "Don't think 'cos I'm talking we're friends" and "Don't think 'cos I understand I care" adds to the rebel-like image of Joan Jett. Musically, the song relies on a backbeat with a piano playing in the background. Originally, the song was a club hit in the UK. After the commercial success and popularity of the album version of the song, several remixes were made of the song. These remixes ended up becoming a hit in dance clubs and radio stations with a dance format. After the release of later songs, "6 Underground" has been the only song to achieve the status of being a crossover hit.