The trio made their major debut in June 2021 with the single "Maybe...YES EP".
On February 1, at the first concert of E-girls' final tour E-girls PERFECT LIVE 2011▶2020, Yokoi Rui, Yamashita Yuna and Sato Hinata were introduced as 3 vocalists of LDH's new girl group "iScream".
On February 19, it was revealed that the three vocalists of the group would be in charge of the ending theme song titled "Maybe...YES" for the Amazon Prime Video drama Ochanigosu. starring Suzuki Nobuyuki.
On April 22, the debut date of the group with their first single "Maybe...YES EP" was announced as June 23, 2021. Additionally, the group pre-released the title song of the single digitally on June 1.
On July 9, the documentary movie iScream Document Movie ~Scream Our Dreams~, which depicts the story of the members from their audition to the debut, started being distributed on iScream's official YouTube channel. While the first episode was released at 13:00 (1 pm), the following episodes will be released every Friday at 20:00 (8 pm).
On August 11, they held their first online live concert titled iScream Debut Online LIVE Show Case, which was broadcasted live simultaneously on their YouTube channel and LDH's video distribution service CL. During the show case, it was announced that they will release their second single "himawari" on September 3.
- Tours featured in
-  E-girls PERFECT LIVE 2011▶2020 (Opening act)
- [2021.08.11] iScream Debut Online LIVE Show Case
- Digital Shows
- [2021.07.09 - Present] iScream Document Movie ~Scream Our Dreams~
- [2021.07.06 - Present] LAUGH & MUSIC ROOM ~iScream Voice~ (FM Osaka, Tuesday 5:30AM)
- The group's name is a play on the pronunciation of words of English and Japanese origin. On one hand, it means "I scream" (私 ( I ) が叫ぶ), on the other hand, it means "Scream Love" (愛 ( Ai ) を叫ぶ). Additionally, interpreting the name as "Ice Cream" could indicate the group's fresh and sweet concept.
- The art visual was drawn with an airbrush by artist Yamaguchi Harumi, a pioneer of realistic illustration.
- HINATA is the only member that was not part of EXPG Lab and its project group KIZZY.