Choi Kang, a new resident of Changri-dong, clashes with youth president Kwak Byeong-nam over recycling issues. He then pursues a suspicious foreigner to clear up a misunderstanding, only to be threatened. During the chase, an unexpected incident unfolds.

Choi Kang is suspected of being a spy after a clash with a foreigner of unknown nationality. While tracking the foreigner's secrets with Kwak Byung-nam and Lee Yong-hee, he discovers an unexpected clue. This clue connects to Choi Kang's past.

A series of mysterious incidents unfold in Changri-dong. Choi Kang, Kwak Byeong-nam, and Lee Yong-hee begin to investigate the truth behind the incidents. The military attempts to cover up the situation, and someone is quietly watching the whole situation unfold.

A video of Kim In-seop exposing the incident goes viral, but no one raises suspicions. Park Jeong-hwan and Jeong Nam-yeon join Choi Kang, Park Byeong-nam, and Lee Yong-hee to uncover the truth behind the incident, and armed forces kidnap Kim In-seop.

Choi Kang learns of the mastermind behind Kim In-seop's kidnapping and, with Kwak Byeong-nam's help, rescues Kim In-seop and takes him to safety. Kwak Byeong-nam, Jeong Nam-yeon, Lee Yong-hee, and Park Jeong-hwan gather there.

A crisis befalls the special forces tracking down clues to Kim In-seop's kidnapping. Their best efforts narrowly save their lives. The recovered evidence reveals a surprising truth, and someone appears before Hwang Mi-kyung and Do-yeon.

Changri-dong, facing a crisis due to the continued pursuit of our neighborhood special forces, is saved by Kim Soo-il's unexpected intervention. Meanwhile, Choi Kang discovers the true mastermind behind the incident.