Season 1

Ordinary high school student Bong-seok hides a secret.

Mi-hyun hides Bong-seok's superpowers, but the mysterious incidents on social media make her anxious.

The closer Bong-seok grows to Hui-soo, the more risk of exposure he draws

Bong-seok's secret is exposed and Hui-soo walks him home. Frank searches for his third target.

Hui-soo assures Bong-seok that his secret is safe by revealing her own secret.

Jeon Gye-do's past is revealed. The NIS finds out information about Frank.

Frank recalls his past as he eliminates his targets. After Frank's visit, Mi-hyun suppresses her son.

In 1994, Mi-hyun is ordered by Deputy Director Min Yong-jun to get close to and learn about the thought process of black ops agent Kim Doo-sik.

Doo-sik and Mi-hyun grow closer, and Doo-sik suggests that they deceive Min Yong-jun.

Ju-won, who leads his gang with his monstrous abilities, is betrayed and becomes a fugitive.

Ji-hee gradually opens up to Ju-won.

Doo-sik shows up at Mi-hyun's apartment with a plan to escape Deputy Director Min for good.

After the Black Team disbands, Ju-won is offered a mission by Deputy Director Min to revive the team.

Jae-man tries to save his wife with his strength and Ju-won is sent in to subdue him.

Mi-hyun and Ju-won watch the auditorium video and head to Jeongwon High, while Gye-do discovers Jun-hwa.

With Mi-hyun's question, Il-hwan reminisces about his past.

Jun-hwa attacks Hui-soo, and Bong-seok awakens his powers to save her.

Mi-hyun asks Deok-yoon where Doo-sik is, and he tells her what happened in the North.

The fight takes a new turn with the appearance of a new North Korean superbeing, Jae-seok.

Parents and children fight to protect each other. Will this repeated war ever end?