Zhang Weijian works in an advertising agency and is often bullied. However, he bears with it, with the aim to retire at 55 years. He gets to know Xiao Kaixin (a.k.a. Big S), an optimistic woman who aims to help as many people as she can. Weijian thinks she is a volunteer worker, but Big S is actually a radio presenter.

Weijian finds out that he has cancer and is torn as to whether he should go for treatment, as the doctor is unable to guarantee his recovery. His friend Dr Cheng Fang encourages him and tells him to discuss his situation with his wife Xiuming.

Weijian contemplates quitting his job and living with more dignity. He decides to apply for several credit cards, and even decided to bring Xiuming on a holiday. Xiuming is shocked at his change.

Weijian celebrates Cheng Fang's birthday and Xiuming mistakes both men having an affair. Weijian asks Cheng Fang to help explain to Xiuming and Cheng Fang brings Big S along. Instead of helping, Big S makes a mess of the situation.

Granny Chen wants to go overseas with her son Deguang but he claims it's inconvenient and doesn't want to bring her. Big S, Cheng Fang and Weijian come up with a plan to make Deguang realize the importance of his mother's love.

Mable tries to pair Big S with Cheng Fang, causing Big S to feel awkward. She shows Cheng Fang her messy room to let him know how incompatible they are. Cheng Fang is scared of dogs and when he sees one, Big S protects him. He falls in love with her as a result but is unable to express his feelings.

Big S does an advertisement and Weijian teases her about being rich. She tells him she isn't getting a lot from the advertisement and even shows him her cheque. He realizes that the amount Big S is getting has a discrepancy and suspects that Ken might be up to something. He decides to check on Ken.

Cheng Fang struggles to express his feelings to Big S, and Weijian suggests he calls in to her radio talk show to seek advice. Big S is unable to recognise Cheng Fang's voice when he calls in. She tells him to record down his feelings and play it back to the girl he likes. Cheng Fang does exactly that, and Big S is left stunned. At this moment, Cheng Fang's ex-girlfriend Wang Jingjing suddenly appears.

Big S tries to turn Cheng Fang off by telling him that he has to go to the SPCA with her to do volunteer work. He looks troubled and Big S tells him he can leave if he wants. He leaves but returns a while later dressed in protective gear to help Big S. She is touched by his action.

Jingjing brings her luggage to Cheng Fang's place, saying that she has nowhere to go as she is facing family problems. Cheng Fang has no heart to decline. Weijian tells him that he's too soft-hearted and is being made use of by Jingjing. Cheng Fang says his feelings for Big S will not change.

Big S tells Cheng Fang that she used to have cancer and her cancer may return anytime. She is unable to say what will happen in the future. Weijian believes that Big S has feelings for Cheng Fang and it took her courage to explain her situation to him.

Weijian decides to pair up Yanzhi and Xiuming. He tells Yanzhi the truth about his situation, in hope that Yanzhi will take care of Xiuming when he passes away. Yanzhi says he is unable to promise Weijian anything and leaves in a hurry.

Big S visits Cheng Fang and sees Jingjing. Jingjing behaves as if she is the lady of the house, and Big S is a little disconcerted. Jingjing is jealous when she sees Big S and Cheng Fang eating together happily. She plots to separate them.

Xiuming hurts herself and requires a blood transfusion. Weijian is unable to do so because of his illness and Yanzhi steps in to help Xiuming. Xiuming is upset. Yanzhi tells Weijian to be honest with Xiuming about his illness.

Jing Jing feels that she's being stalked by her ex-boyfriend Alex. Cheng Fang tells her not to think too much. As she is preparing to move to her new place, she is harassed by someone. Cheng Fang is worried about her and has no choice but to ask her to continue staying at his home.

Xiuming falls sick and doesn't turn up for work. Yanzhi is worried and looks for her at her home. He takes good care of her, leaving Xiuming feeling very touched. She is upset that Weijian seems indifferent to her.

Big S realizes that Jingjing has been pretending to be scared all this while. Jingjing tries to beg Cheng Fang for forgiveness without avail. In a fit of jealousy, she tries to stab Cheng Fang but ends up stabbing Big S when Big S tries to protect Cheng Fang.

Big S recovers, much to everyone's relief. Cheng Fang's parents are grateful to her for saving their son's life. Yanzhi tells Xiuming how he feels about her but Xiuming isn't ready to accept another man yet.

Weijian plans a funeral party for himself, and invites long-lost friends and relatives. However, his health has been improving and when he goes for a check-up, he is told that his cancer cells have disappeared!

Jingjing kidnaps a visually-impaired girl An An to lure Big S to an isolated building. Big S refuses to be threatened by Jingjing and in the scuffle, Jingjing accidentally sets fire to herself. To save An An, Big S jumps out of the burning building...