U45: Book 1 and 2

Season 1 Episode 4 (June 23, 2018)

This episode starts with a playback of the third episode. The footage shows some of the group battle performances and the live and online rankings where Trainees Chou Tzuyu (추쯔위) and Kim Jun Myeon (김준면) dominated it, resepectively.

The trainees enter the studio by label. Then, Representative Park arrives and shows the contestants their hidden cam footage including the fitness challenge and diet plans.

The fitness challenge included footage of the trainees running to the training center. There, they gathered and met Tiffany Young, former member of Girls' Generation and she taught them exercises.

Meanwhile, after doing the fitness exercises they got their BMIs measured. Those who gained a lot were sentenced to a strict diet plan. This means that they are only allowed to eat the prepared meals in The G Restaurant, which includes fruits and vegetables. However on the other hand, the other trainees are free to eat as many as they can. Because of this, some trainees got envious of them.

After that, the inside footage of their dormitory life was revealed. This included their sad and funny moments together.

After the showing of the hidden cam footage, she starts in announcing the rankings. After calling Rank 5, she reveals the Top 4. They are Trainees Chou Tzuyu (추쯔위), Kim Jun Myeon (김준면), Park Ji Hoon (박지훈), Park Ji Hyo (박지효). Therefore, Trainee Chou Tzuyu of JYP Entertainment surprisingly takes first place with 316,094 votes in all.

Then, the 4 candidates for the last seat, Rank 36 are revealed. These are Trainees Ha Sung Woon (하성운), Min Yoon Gi (민윤기), Park Ji Min (박지민), and Son Chae Young (손채영). Trainee Park Ji Min (박지민) of Big Hit Entertainment is saved from elimination after garnering 31,902 votes.

Then, Representative Park reveals the rankings of the remaining 9 trainees.

Meanwhile, the Top 36 bid goodbye to the 9 trainees that will be eliminated. They shed tears and promised each other that they will see each other soon.

After the ranking announcement, they are gathered in a function room once again seeing a wall covered by curtain. What are they doing there?

This episode ends with a cliffhanger. Representative Park announces their next mission with some in a state of shock.