The first mission was revealed: the nine members were challenged to compose their own song and showcase a performance to determine if they could debut altogether or if an elimination is inevitable. One week prior to their performance, the other members started moving into their dorm. After they settled in, the group went to the arcade to spend some free time. At JYPE Training Center, the group selected the track they would use for the mission evaluation and started practicing. On the day of the evaluation, the group announced their name, Stray Kids, and their song titled 'Hellevator'. After the performance, Park praised the song's lyrics, arrangement and melody, though he mentioned that the key of it is too high for male singers. There were members who did not meet Park's standard and expectation, which led to an elimination round.
