When the Underneath disbanded in 2010,[2] most of the group was signed to Avex Mode to perform songs for the Kamen Rider Series.
The Wilma-Sidr line-up then reunited under the name Defspiral on Avex Group's Avex Mode label and released the single "Dive into the Mirror", the opening theme song for TV Asahi broadcasts of Kamen Rider: Dragon Knight.
[4] The group's debut album Progress was released in late October 2011, showing a stronger musical style with only the solo guitarist.
[5] On December 7, Defspiral released a 4-track maxi single titled "Reply -Tribute to hide-" as a tribute to the late hide, who signed the members' previous band Transtic Nerve to his label.
[7] After being with Transtic Nerve, the Underneath and defspiral since 1995, founding member and drummer Masaki left the band on May 26, 2021 after their 10th anniversary tour final Dearest Freaks at Tsutaya O-West.