Season 1

Chinese restaurant delivery man, Kang-soo, has just arrived in a new town for an interview. He soon finds himself bickering with a new face, Dan-ah.

Ji-yoon leaves home and pushes her way into Kang-soo's new room above the restaurant. Dan-ah is surprised when she enters to find women's clothing.

After saving Jin-gyu's life Dan-ah is furious to hear him say he's fed up and wants to die. She's worn out at work too and finds herself hospitalized.

Dan-ah sees her dream of moving abroad draw closer as Jin-gyu agrees to pay her a gesture. Kang-soo is chasing down who caused Hyun-soo's accident.

With help from a large group of bikers, Kang-soo wants proof Jin-gyu was part of the illegal road race. He gets a crime-scene video to put out on TV.

Jin-gyu is back in town to manage a rival restaurant. Kang-soo demands prosecutors explain Jin-gyu's release, but he is charged for interference.

Kang-soo confesses to attacking Jin-gyu. Sung-jae reveals it was really him, but with so many others trying to take the blame, Kang-soo is locked up.

Kang-soo holds Dan-ah and tells her he missed her, she's cold and runs out on him. He drinks with Jin-gyu and persuades him to apologize to Hyun-soo.

Kang-soo declares he'll stay by Dan-ah's side until she goes abroad. Meanwhile Ji-yoon manifests as a rival presence to Dan-ah.

The Strongest Delivery Man company is up and running, Kang-soo and the guys get to work. Dan-ah is fired and reluctantly starts working with the guys.

Going after Jeong-im, Kang-soo goes out of town, he gets a revelation when he meets Hyun-soo's mother. Jin-gyu and Ji-yoon go on a long-awaited date.

A restaurant signs up for Kang-soo's app business. His closest rivals are shaken. Jin-gyu cuts a disheveled figure as he wanders around town homeless.

On a staff outing, Kang-soo tells Dan-ah how he feels with a kiss. She's confused, but goes home happy. Ji-yoon pushes Jin-gyu into living with her.

After Dan-ah admits her love for him, our hero is spurred on with new business ideas. What's more, encouraged by Ji-yoon, Jin-gyu joins the venture.

The Strongest Delivery Man wins a big contract and Kang-soo and Dan-ah's relationship is blossoming. But business rival, Hye-rin, gets in the way.

Dan-ah goes after Kang-soo who left a farewell note before leaving Seoul. She persuades him to return and the team agrees to Jin-gyu's business idea.