R. City (short for Rock City; and formerly Planet VI) is an American hip hop duo formed by two brothers Theron "Uptown AP" Thomas and Timothy "A.I." Thomas in 2003. Primarily known as a songwriting and record production team, the duo amassed numerous credits for prominent music industry acts prior to signing with Kemosabe Records, an imprint of RCA Records in 2014 as recording artists. The following year, their single "Locked Away" (featuring Adam Levine), peaked at number six on the Billboard Hot 100 and preceded the release of their debut studio album, What Dreams Are Made Of (2015).

Prior, the duo signed with Akon's KonLive Distribution, an imprint of Geffen Records in 2007, having received their first commercial songwriting credit for the singer. Due to the long-term delay of their scheduled debut album for the label, Wake the Neighbors, they released the mixtape series PTFAO (Put the F*ckin' Album Out). Their 2008 debut single, "Losin' It" failed to chart. The duo parted ways with KonLive in 2011 and continued their songwriting work. Since signing to Kemosabe, they often collaborate with label boss Dr. Luke to jointly co-write songs of which he produced.

While releasing solo material, R. City wrote and produced for various artists including Sean Kingston ("Take You There"), Miley Cyrus ("We Can't Stop"), Nicki Minaj ("Only") and Rihanna ("Pour It Up"). The duo has also contributed to several Grammy Award-nominated albums, including Rihanna's Unapologetic (which won Best Urban Contemporary Album), Jennifer Hudson's self-titled album (which won Best R&B Album), and Ariana Grande's My Everything (which was nominated for Best Pop Vocal Album). Theron won the Songwriter of the Year, Non-Classical at the 66th Annual Grammy Awards for his credits throughout 2023.