Seo-jin is a widower still grieving his wife's death. Then he receives the news that his long-lost younger sister, Yoo-jin, who went missing 25 years ago, has turned up. Unlike the rest of his family, who welcome her into their arms, Seo-jin feels that Yoo-jin is a stranger.
Min-jae, a rookie police officer with a natural born talent for driving, is assigned to the perfect team: the Hit-and-Run Squad. But at the same time, for police detective Si-yeon, it is a place she is unjustly demoted to for doing her job. The two team up to arrest the rich and powerful speed maniac Jae-chul who is suspected of committing crimes for his obsession for speed.
Woo-ri, 32, and Ja-young, 28, who both dislike being alone but have particular anxieties when it comes to dating, meet through an app.
