Utsuki, Rin and Mio start taking lessons to train to be Mika’s back dancers. It’s a long, hard struggle, but thanks to the encouragement of the other project members, they somehow make it. But the pressure of being on stage for the first time has stressed the trio out so much that even the final rehearsal doesn’t go well. Will they be able to get it together for the actual concert?

The trio of Rika, Miria, and Kirari make their debut as Dekorationt and even do a tie-in with the fashion brand Pika Pika Pop. The unit does fine with a PR event, but Producer feels they can involve the audience more. While thinking of ways to do just that, the trio takes a breather in Harajuku, but when Producer gets separated from them, both sides look in all the wrong places for each other. The clock is ticking too, since the next event starts soon, so never mind engaging the audience, Dekoration may miss the whole thing!

Miku and Riina are concerned with improving as a unit to get ready for “Cinderella’s Ball,” despite their usual clashes over the direction of the unit. Meanwhile, Riina becomes friends with a rock idol she admires, Natsuki Kimura, whom Executive Director Mishiro has invited to join a new rock-idol unit.

Connecting with Natsuki, who is devoted to rock, makes Riina remember how much she loves it too. Riina is torn over what she wants to do. Miku picks up on the fact that Riina isn’t her usual self and worries about her partner, but decides to wait until she is ready to talk...

Uzuki has lost sight of herself and lost her smile, but Mio and Rin still believe in her, so they wait for Uzuki to come around. In response to her friends' faith, Uzuki visits 346 Pro, but she still has no good answer to the indecision that's inside her. Mio and Rin decide to watch over Uzuki, who remains in doubt even as she takes a lesson at the office. Afterwards, the other members on the scene share their various feelings as colleagues, friends, and idols.

The encounter makes Uzuki think about what she's currently missing. And then it's Christmas Eve. Producer picks Uzuki up and they head over to the concert venue, but stop off at a certain place along the way...

Unaired episode bundled with the ninth Blu-ray and DVD volume of The iDOLM@STER Cinderella Girls.