Singer Mika Nakashima is collaborating with female comedy trio Morisanchu, putting together a rock band called "MICA 3 CHU" (Mikasanchu). They will release a single titled "I DON'T KNOW" on July 23, though 5 different ringtone versions were made available already on Tuesday.

Nakashima proposed the project herself after having appeared with the three comediennes on the television program "Utaban." She is in charge of the main vocals, backed by Miyuki Oshima on guitar, Tomoko Murakami on bass, and Kazuko Kurosawa on drums. Nakashima herself wrote the all-English lyrics, which are said to be partly inspired by her recent breakup with actor Masatoshi Nagase.