Roots of Ai

Judith Glory Hill is an American singer-songwriter from Los Angeles, California. She has provided backing vocals for such artists as Michael Jackson, Prince, and Josh Groban. In 2009, Hill was chosen as Jackson's duet partner for the song "I Just Can't Stop Loving You" during his This Is It rehearsals. After Jackson's death in 2009, she, along with the rest of the This Is It cast members, performed at Jackson's memorial service and attracted global attention when she sang the lead on the song "Heal the World". Hill's rise to fame is recounted in 20 Feet from Stardom, a documentary film that tells the untold story of the backup singers behind some of the "greatest musical legends of the 21st century". She is also a featured artist on the film's soundtrack. She won the Grammy Award for Best Music Film for her performance.

Hideyuki Yokoi , known professionally as Zeebra , is a Japanese hip hop rapper and DJ who made his first appearance in 1995. Zeebra is a former member of the hip-hop group King Giddra, which also included DJ Oasis and K Dub Shine. He went on to pursue a solo career shortly after in 1997, and signed with the Future Shock record label.

Joseph Anthony Budden II is an American broadcaster and former rapper. He first gained recognition with his 2003 single "Pump It Up", which peaked in the top 40 of the Billboard Hot 100 and preceded the release of his eponymous debut studio album (2003). A critical and commercial success, the album peaked in the top ten of the Billboard 200, although it was his only major label release for Def Jam Recordings. He released seven more independent albums to continued critical praise. While doing so, he performed as a member of the hip-hop supergroup Slaughterhouse, who signed with Eminem's Shady Records in 2012; the group released two studio albums. In 2014, he was made fun of in episode nine, "Tombstone," of Loiter Squad's third season, with his beard divorcing him, played by rapper Earl Sweatshirt.

Double was a Swiss music duo best known for their hit single "The Captain of Her Heart".