The ten candidates for the next NCT unit are introduced along with SION and YUSHI, the fixed members.Revealing the whole process of SM idols’ debut! SM’s first-ever survival show, NCT Universe : LASTART, will select the last unit of NCT, an ever-expanding group. The top artist directors have come together for the new NCT team. Asia’s number 1, BoA, King of the Korean wave, Eunhyuk of Super Junior, a special artist director, KEY of SHINee. SMROOKIES, SION and YUSHI, whose debut is confirmed, and ten trainees who must seize the chance to debut. Their first step is the two-member stage mission. The trainees’ skills are revealed for the first time with tension in the air. How will they be evaluated through the first mission? The trainees’ new start to debut as the last unit of NCT, NCT Universe : LASTART.

The trainees continue to present their performances for the two-member mission. Their rankings get revealed. The first step toward the ten trainees' debut, the two-member stage mission! The SM trainees present vocal, rap, and dance performances with tension in the air. The artist directors give favorable comments and harshly criticize them as well. An appearance of a trainee with a tone that’s never been heard in SM? The rankings of the first mission finally get revealed! A special benefit for SMROOKIES and the top four trainees is revealed! Who will be the TOP4 that gets closer to their debut as NCT’s new team? The trainees’ new start to debut as the last unit of NCT, NCT Universe : LASTART.

The second step toward the ten trainees' debut, Group Mission with SM Hits! Which mission songs among numerous SM hits are given to SMROOKIES and the ten trainees? Revealing the whole process of team selection, practice, and behind-the-scenes of the trainees who are divided into two groups. Which guests secretly visited SMROOKIES and the trainees, who were practicing for Group Mission with SM Hits hard, and surprised them? The best solo male artist, the master of unrivaled performance and stage themes, TAEMIN of SHINee. And a one-point lesson from Dong Hae of Super Junior, an all-round entertainer who can dance, rap, sing, and compose. The trainees keep making mistakes during rehearsals as they are nervous. Will SMROOKIES and the ten trainees be able to finish their performances successfully?

The second gateway to their debut, Group Mission with SM Hits, has not ended. Team “U” starts their performance while still feeling anxious from their rehearsal. Will they be able to pull it off in their own style in front of Eunhyuk and Ryeowook, the original artists? The rankings for the second mission get announced amid tension. Who are the TOP 4 that will get the second benefit with the two SMROOKIES members? A different practice room unfolds before SMROOKIES and the ten trainees. Their playfulness gets revealed! And a new trainee is suddenly included. The appearance of the 11th trainee! The fiercer and more intense fate of the 11 trainees will unfold!

The trainees continue with the missions without any room to breathe. The third gateway to their debut, Group Mission with SM Hits in Japanese. SMROOKIES and the 11 trainees practice day and night after receiving even more difficult mission songs. The trainees have a hard time getting the formation and rhythm right. Will they be able to prepare a perfect stage? The original singers are here to pass on tips on the formations and details. K-pop’s representative idol, EXO’s XIUMIN, who has a sweet voice and dominating performance skills. And the pioneer of the Korean Wave who owns all sorts of records, Chang Min of TVXQ. Team “Electric Kiss” by EXO and Team “Why?” by TVXQ are about to perform the SM Hits in Japanese. The air is super tense between them! Will they be able to present the best stage while pulling off the most difficult performance?