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.
Episode credits
Guest stars Lee Young-ae, Choi Won, Zo Zee-an, Park Seong-geun, Yoon Seok-hyun, Lee Eun-joo, Yoo Joon-hong, Jang Won-hyuk
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.
Episode credits
Guest stars Choi Won, Zo Zee-an, Park Seong-geun, Yoon Seok-hyun, Lee Eun-joo, Kim Jo-yeon, Lee Kyu-ho, Koo Ja-geon
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.
Episode credits
Guest stars Lee Young-ae, Byun Joong-hee, Ko Sang-ho, Kang Young-taek, Yoo Dong-Hun, Oh Jin-seok, Shin Kang-kyun, Yoo Ah-reum
Rainbow Transport officially begins its operation to bring punishment to Sang-gi. The plan mainly depends on Sung-cheol being a loaded old man as bait. As soon as Sang-gi sees this and plans to scam him, he does not realize the karma that he is about to face. Meanwhile, the secret organization Do-ki is after is also keeping an eye on Do-ki as well.
Episode credits
Guest stars Byun Joong-hee, Ko Sang-ho, Kang Young-taek, Yoo Dong-Hun, Woo Sang-jeon
Do-ki runs into a stray little girl on the street. Out of concern, he takes her to Rainbow Transport and learns that suspicious people are after her. Do-ki and the team tries to infiltrate Feel Consulting and get some info on Kang Pil-seung to find out why he is in search of this poor little girl.
Episode credits
Guest stars Ahn Chae-heum, Kim Do-yoon, Ahn Seong-bong, Jung Young-ki, Ok Yoon-Joong, Jang Joon-yeong
Do-ki and Go-eun get busted by Pil-seung for putting up an act. However, Do-ki manages to win back his trust by acting how desperate he is for a house. Now that they are back on track, Do-ki learns how Pil-seung is able to help couples get housing by using children. Disgusted by his ways, the team is determined to bring down Pil-seung at all costs.
Episode credits
Guest stars Ahn Chae-heum, Kim Do-yoon, Ahn Seong-bong, Jung Young-ki, Ok Yoon-Joong, Lee Da-hye, Kwon Na-hyun, Yoon Man-dal
The next client is a woman named Lee Jin-hee. Her beloved sister Jin-sun is suffering from a terminal disease and is relying on a cult to cure her. To save her from the cult and to take down its leader, Rainbow Transport begins service. However, Do-ki is not the one who will be infiltrating the cult this time.
Episode credits
Guest stars Lee Young-ae, Ahn Sang-woo, Kim Eun-bi, Jung Ji-woo, Seo Ji-soo, Park Jong-hwan, Park Bu-keon, Kim Sun-hye
The plan to destroy Ok Ju-man is now set. The only thing that remains is for Ju-man to take the bait. Although he does not have faith in any kind of religion, the Rainbow Transport team makes it seem believable. By setting the perfect scam, Ok Ju-man becomes faithful to the fake cult that Do-ki makes.
Episode credits
Guest stars Ahn Sang-woo, Kim Eun-bi, Jung Ji-woo, Seo Ji-soo, Kim Sun-hye, Kim Jin-ok, Kim Su-ol, Park Sang-hoon
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.
Episode credits
Guest stars Yoo Seung-mok, Park Jong-hwan, Namkoong Min, Lee Hang-na, Jeong Gi-seop, Kang Seol, Kim Yong-jin, Kim Jae-min
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.
Episode credits
Guest stars Park Jong-hwan, Lee Hang-na, Jeong Gi-seop, Kang Seol, Kim Yong-jin, Kim Jae-min, Lee Ha-joo, Jang Eun-seo
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.
Episode credits
Guest stars Park Jong-hwan, Lee Jung-yeol, Baek Soo-jang, Ko Gun-han, Moon Jae-won, Lee Dal, Kim Chae-eun, Yoo Ji-yeon
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.
Episode credits
Guest stars Park Jong-hwan, Baek Soo-jang, Ko Gun-han, Moon Jae-won, Lee Dal, Kim Chae-eun, Yoo Ji-yeon, Jeon Kwang-jin
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.
Episode credits
Guest stars Park Jong-hwan, Ko Gun-han, Moon Jae-won, Lee Dal, Kim Chae-eun, Yoo Ji-yeon, Jeon Kwang-jin, Jeon Woon-jong
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.
Episode credits
Guest stars Park Jong-hwan, Baek Soo-jang, Ko Gun-han, Moon Jae-won, Lee Dal, Kim Chae-eun, Yoo Ji-yeon, Jeon Kwang-jin
Rainbow Transport takes in another client. However this time, it is a set-up made by the Bishop and Ha-joon. Not knowing that it is a trap, Do-ki blindly goes into Jangsan Correctional with Kyung-goo and Jin-eon to save a victim. The only thing that is waiting for him is Ha-joon's trap that will break Do-ki into pieces.
Episode credits
Guest stars Park Jong-hwan, Park Ho-san, Jeong Seung-won, Kim Chang-hwan, Kang Gu-ha, Jo Seung-goo, Geum Gwang-san, You Il-han
Do-ki goes into Jangsan Correctional as an undercover inmate. He fights all the way through every trap that Ha-joon has prepared for him. Although he barely makes it in one piece, he saves Lee Si-wan. Meanwhile, Ha-joon learns about his true identity and what the Bishop has done to him since his childhood.
Episode credits
Guest stars Park Jong-hwan, Park Ho-san, Moon Chae-won, Kim So-yeon, Jeong Seung-won, Kim Chang-hwan, Kang Gu-ha, Oh Sang-ho
