A world-class hitman ends up swapping identities with a down-to-luck extra actor during an accident.

In the graduation season in July, the life's most perfect summer and the most enthusiastic summer, every young person is embracing the future's vast carnivals as much as one's heart can. Independent and freedom loving Gu Youyou loves street dancing, is learning ballet as it is what her mother wishes. In everyone’s youth, there is hesitation and passion, but they all have to face the final choice. Encouraged by her boyfriend Mao Xueshan, Gu Youyou decides to take the step of pursuing her dreams and refused the invitation of the Central Ballet Company... The intense conflict between family affection, love, and dreams made the summer of the graduation season lively.

Three men are thrown together by a toddler who comes out of nowhere, disrupting their already stressful lives. The loyal and kind-hearted Gao Han (Bosco Wong) has just lost his legal battle with his ex-wife for custody of their daughter. His ex-girlfriend and first love, Guan Lingling (Shirley Dai), who died in a car accident, has just sent her son to live with him. Gao Han and his two tenants Wang Dongyang (Liu Guanxiang) and Yu Bo (Luo Yunxi) suddenly find themselves becoming nannies to a child, Dudu (Zou Zichen). Not only must they look after this little one, they must deal with an even bigger headache- Dudu's aunt Guan Shanshan (Kan Qingzi). While the three grown men busy themselves with raising Dudu, they try to determine the child’s paternity. They undergo a custody battle, as they deal with issues tied in with the return of Han's ex-wife’s Liu Min (Mai Hongmei). Han and Shanshan develop feelings for one an other. To complicate matters, Yu Bo also falls for Shanshan.