Matt McJunkins is an American musician and photographer best known for touring and recording with the American rock band A Perfect Circle. He is a former touring bassist for Eagles of Death Metal. He is one of the founding members of The Beta Machine, a rock band formed with Jeff Friedl. McJunkins has also worked with Thirty Seconds to Mars, Ashes Divide, Puscifer, Poppy and Socadia.

A Perfect Circle is an American rock band formed in Los Angeles, California in 1999 by guitarist Billy Howerdel and Tool vocalist Maynard James Keenan. A Perfect Circle released three of their four studio albums in the early 2000s: their debut Mer de Noms in 2000, a follow-up, Thirteenth Step in 2003; and an album of radically re-worked cover songs, Emotive, in 2004. Shortly after Emotive's release, the band went on hiatus; Keenan returned to Tool and started up solo work under the band name Puscifer, while Howerdel released a solo album, Keep Telling Myself It's Alright, under the moniker Ashes Divide. Band activity was sporadic in the following years; the band reformed in 2010, and played live shows on and off between 2010 and 2013, but fell into inactivity after the release of their greatest hits album, Three Sixty, and a live album box set, A Perfect Circle Live: Featuring Stone and Echo in late 2013. The band reformed in 2017 to record a fourth album, Eat the Elephant, which was released in 2018. After spending the rest of the year touring in support of the album, the band fell into inactivity until 2024 for a brief tour and one-off song "Kindred".