"Idol Memories" is a 12-episode anime series set in a futuristic world where virtual idols dominate the entertainment industry. The story centers around the members of the idol unit "LizNoir," who are managed by the talent agency Sirius Entertainment. The series explores the challenges and aspirations of these idols as they navigate their careers in a highly competitive and technologically advanced environment.

The narrative begins with the introduction of LizNoir, a group of six young women: Kotono Nagase, Ruri Hijiri, Ai Saegusa, Kokoro Saegusa, Yui Mitsumine, and Rin Kurosawa. Each member has a distinct personality and background, contributing to the group's dynamic. Kotono, the main protagonist, is a cheerful and determined girl who dreams of becoming a top idol. Ruri is a calm and composed leader, while Ai and Kokoro are twin sisters with contrasting personalities—Ai is energetic and outgoing, while Kokoro is shy and reserved. Yui is a former child actress struggling to redefine her career, and Rin is a mysterious and aloof member with a hidden past.

The plot unfolds as LizNoir prepares for the annual "Idol Festival," a prestigious event that determines the ranking of idol units. The competition is fierce, with rival groups like "Trinary" posing a significant threat. Throughout the series, the members of LizNoir face various challenges, including personal insecurities, rivalries, and the pressure to succeed. The story delves into their individual growth and the bonds they form as a team, highlighting themes of perseverance, friendship, and self-discovery.

A key element of the series is the integration of advanced technology, such as holographic performances and virtual reality, which play a significant role in the idol industry. The series also touches on the ethical implications of technology, particularly through the character of Rin, whose connection to a secretive research project adds a layer of intrigue to the narrative.

As LizNoir progresses through the Idol Festival, the stakes rise, culminating in a dramatic finale where the group must confront their fears and insecurities to deliver a performance that will define their future. The series concludes with a resolution that emphasizes the importance of teamwork and staying true to oneself, leaving the characters poised for new challenges and opportunities in their careers as idols.