A smelly drunk man protests alone in front of a big hospital. He claims that his daughter is in a coma due to a surgery malpractice. Although Rainbow Transport took him in as a client, they are not sure whether this is an actual case or just an accident. Before they start anything, Do-ki looks into Ahn Young-sook, the director who performed the surgery.

Do-ki becomes a patient himself to infiltrate the operating room. When he is put to sleep, Go-eun finds out that there is a proxy who does the actual surgery while Young-sook goes somewhere else for a drink. Now that the team knows she is a complete fraud, they set up a meticulous plan to bring the witch down.

Do-ki makes it out alive from the car bomb explosion. He uses his death to track down the person behind the vicious attack. While his funeral progresses, Do-ki and the team monitor any suspicious people coming and going, which leads them to a club for the rich in Gangnam. Do-ki makes his entrance to find out more.

After Do-ki gets kicked out from Black Sun and gets beaten up, the police arrive. However, the police arrest Do-ki instead. Although Yong-min helps him to bail out, Do-ki now knows that the police are working with Black Sun. Rainbow Transport infiltrates the club to take them down for all the crimes they are committing.

An angry VIP client at Black Sun puts the security team on edge. The security team gets a second chance to make another delivery. Only this time, Do-ki joins the team. What he learns is shocking. Meanwhile, Sung-cheol digs into Ha-joon's past.

While Do-ki wakes up from getting drugged, the bishop comes back to Korea. Now that Do-ki has evidence of how Black Sun is circulating drugs, he sets up a plan. Meanwhile, Ha-joon notices that Rainbow Transport is on Black Sun’s tail. Knowing how skillful Do-ki is, he takes every precaution he can take.

Despite the disbandment of Rainbow Taxi, Do-ki is still out there going after bad guys. While keeping it from the rest of the members, Do-ki and Sung-cheol secretly help out a father who is searching for his missing son. To confirm his whereabouts, Do-ki sets off abroad to a foreign country to accomplish his first mission.

Do-gi finds himself in danger after Yang-jin gives him a cruel test of loyalty. Go-eun returns to locate and destroy the data servers.

While Ha-na looks into allegations of employees suffering physical abuse inside a powerful tech company, Do-gi poses as a new recruit there.

Shaken by an abusive experience, a young woman with an intellectual disability takes up the services of Kim Do-gi and his team of revenge seekers.

With an eye on payback, Do-gi transforms into a deep-pocketed customer to trick Kang Maria's tormentors. Kang Ha-na wonders about a missing criminal.

Do-gi goes undercover as a high school substitute teacher after receiving a call for help from a student who is being severely bullied.

The three bullies' attempts to mess with Do-gi come to a halt when they realize he possesses video footage that could ruin their lives.

As the truth behind an exploitative incident involving An Go-eun's sister comes to light, Do-gi sets out for revenge. Ha-na shows up with a warrant.

Ha-na grows suspicious when she finds Do-gi's ID card at the scene of the explosion. Meanwhile, the team takes on a phone scam case.

When Yeong-mi comes after the team, Do-gi throws himself into action to save them from her cruel clutches before it's too late.

To gain access to Park Yang-jin's inner circle, Do-gi focuses his efforts on infiltrating a key department within the company.

Do-gi dons another disguise to lay his charms on the leader of the voice phishing operation. Ha-na keeps a close eye on the team's whereabouts.

Certain that Jang Seong-cheol and his employees are hiding something, Ha-na storms his home. A pastor worries about his missing son.

In mourning, Ha-na goes to Do-gi as a client in search of vengeance. While investigating, the team uncovers a larger scheme at play.

The team pulls together for one final mission to nail the true culprit behind the death of Do-gi's mother. Ha-na attempts to resign.

The team is taken by surprise when Baek Yeong-mi empties the secret prison cells. Do-gi plans to use Gu Yeong-tae as a bargaining chip.

It's the end of the road for Seong-cheol and the team as they agree to shut down their operation. Do-gi is made to face the demons of his past.

Do-ki successfully infiltrates Cheongeum with the help of his old crew. He pretends to be an abducted recruit but secretly searches for Dong-jae. During the search, he runs into Lim Bok-ja. He uses her revengeful anger to make it easier to find the missing boy. Just when he is about to capture the mastermind, a mysterious gun shot interrupts his arrest.

An elderly woman visits Rainbow Transport as a victim. She owes a lot of money because of a young scammer who only rips money off old people. Do-ki and the team get infuriated upon seeing this and set up a plan to prevent this criminal from ever scamming the elderly again.