One Ok Rock (stylized as ONE OK ROCK) is a Japanese rock band formed in 2005, composed of Taka, Toru, Ryota, and Tomoya. Originally a five piece band, guitarist Alex left the group in 2009.2005-2006: Formation and Early DaysThe foundation for One Ok Rock began when Toru Yamashita, then a high school student, wanted to start a band. He told his friend Ryota Kohama, a fellow member of the hip hop dance group Heads, to learn the bass and asked Alex Onizawa, who was their senior in school to join. He asked his classmate Tomo to play drums, but he left the band in 2006 to pursue an acting career. At that time, Taka Moriuchi was playing with another band named Chivalry of Music; however, Taka didn't enjoy playing with them, so Toru insisted that he join One Ok Rock instead. After signing with a label, Amuse, Inc. Tomo left the band because his parents didn't want their son to walk in this way. Tomoya Kanki actually had been teaching in ESP (Musical Academy) and have a band. Same with Taka, that band isn't going well. Then he has joined with them since 2006, but only became an official member when they debuted in 2007.The band's name, One Ok Rock, comes from "one o'clock", the time that the band used to practice on weekends. However, noticing that the Japanese language made no distinction between r's and l's, they changed "o'clock" to "o'crock" (or "o'krock"), which was then separated to become "ok rock".2007-2009: Debut Album and Old FormationTheir debut single, Naihi Shinso surprisingly reached positions 48 on Oricon Chart and sold out 15,000 copies. Second single, Yume Yume followed that successful and reached position 43. After those singles, finally they released their debut album Zeitakubyo in 2007. This is their first time had a tour and played in many cities. Not long after that second album, Beam of Light released in May 2008. In interview with Rockin'On Magazine in June 2012, ONE OK ROCK didn't count this album as an album, but a part of growing up as a band. When they made this album, they weren't in the mood to make it, but they must make a song. That is the reason why until now they wouldn't play any songs from Beam of Light in live performances. It has been planned for releasing two albums in one year, so they released Kanjou Effects in November 2008. Shortly after release of Beam of Light they attend a gig in Shibuya AX and recorded as a DVD.On April 5, 2009, Alex was arrested for groping the leg of a twenty-one-year-old female student on a train. He admitted to the charges and the case was settled out of court. However, the band's next single "Around the World Shounen", which was planned for a May 6 release and to be used as the theme song for the TV drama God Hand Teru, and their nationwide tour were both cancelled. In May 2009, it was announced that One Ok Rock would continue without Alex.2010: New FormationWith four-formation, the band released the single "Kanzen Kankaku Dreamer" on February 3, 2010. It reached 9th on the Weekly Oricon Chart. They released their fourth studio album titled Niche Syndrome on June 9, 2010. Their next single, "Answer is Near", was released on February 16, 2011.The band released their first double A-side single "Re:make/No Scared" on July 20, 2011, the latter song being the main theme for the Black Rock Shooter: The Game video game. The band's fifth album, Zankyo Reference, was released on October 5, 2011. Their latest single, "The Beginning", which is used as a theme for the live action movie adaptation of the Rurouni Kenshin manga, was released on August 22, 2012.In January 12, 2014 their album producer John Feldmann tweeted that ONE OK ROCK already started recording the new album.