On January 4, 2017, Top Secret debuted as a seven member group under KJ Music Entertainment[2] with the mini album Time's Up.

His management agency denied the accusation, when the victim's online post began to circulate after his debut with the group.

[11] On February 11, 2019, TST released the extended play Wake Up, which shares the same name as their second mini album.

[12] Wooyoung didn't take part in the EP and in the subsequent releases due to health issues.

[13] On February 20, 2019, KJ Music reported through TST's fan cafè that member K would be enlisting in the military to complete his mandatory service on March 21, 2019.