She has no personal life, and her life only revolves around the kitchen.
Workaholic and perfectionist, her entire life follows a strict order in which there are hardly any unforeseen. Her obssesion with the kitchen and the preparation and presentation of the dishes, makes her an exaggerated perfectionist. That's why her boss Paula says she will fire Kate unless she goes to therapy. But Kate, even agreeing in going to therapy, is oblivious about her obssesion.
But her calculated, distant and impersonal life is turned upside down when Kate's sister is killed in a car accident. Kate's nine-year old niece, Zoe, must move in to live with Kate as it was Kate's sister wishes if something happened to her.
Kate feels devastated by her sister's death, and she's overwhelmed with work and the child care.
But little by little she puts in a new order her priorities: she breaks down the barriers in her personal life, and allows herself to become vulnerable. She decides to take risks in the personal affairs, she accepts the help of the new suchef of her kitchen (who at first saw him as a rival) who is in love with her. And they both fall in love.
Yet life hits her hard when Paula decides to offer Nick the job of head chef and Kate's relationship with Nick turns a sour note due to Kate's pride.
In the end, Kate definately tears down the walls she has built throughout her life so that she and Nick could start fresh. The movie concludes with Zoe, Nick and Kate having opened their own bistro.
Catherine Zeta-Jones portrays Kate as a controlling woman who lives only for her work. But she hides her feelings because she doesn't want to be hurt (it's dropped that she has suffered many disappointments) so she wants to be in the "safe zone".
But with the arrival in her life of her niece Zoe, whom she will have to take charge of, and the arrival of the charismatic and uplifting Nick to her kitchen, she will soften her heart and allows herself to start a family with them.