Detective Lee Sang-won (Sung Dong-il) and his daughter, Lee Jang-hyun (Kim Yoo-jung), meet high school teacher Nam Chul-woong (Son Ho-jun) and discover common ties to a tragic murder case that happened 10 years earlier.
Noh Ae-jung (Song Ji-hyo) is a single mother with a strong survival instinct who has been single for 14 years. All of a sudden, four men who appeal to her in different ways appear in her life. She had past friendships and relationships with three out of four of these men before her pregnancy. Oh Dae-oh (Son Ho-jun [URL:https://en.wikipedia.org/wiki/Son_Ho-jun]) is a bad but attractive man, Ryu Jin (Song Jong-ho) is pathetic but handsome and rich, Goo Pa-do (Kim Min-joon) who is scary and sexy, and Oh Yeon-woo (Koo Ja-sung [URL:https://en.wikipedia.org/wiki/Koo_Ja-sung]) is a flirty younger man.