In order to get through the heart-wrenching days after the breakup, Jane frantically searched for the reason why Lei had changed his love in all aspects. Eventually she felt she had found a reason in the animal world. She found an uncanny resemblance between men and their "animal brothers." Jane began to study animal mate-seeking habits.
Jane retreated from her apartment because she was planning to live with Ray, but now she must find a new place to live as soon as possible. She is thrilled that she will find this so-called "home" in the most unexpected place: not only does her girly colleague Eddie Elton (Hugh Jackman) give up a room. The bedroom is for her to live in, and more importantly, it also provides a typical "sample" for her to study "male animals".
Jane tells her friend Liz (Marissa Tomei), who is also a single woman, about what she has learned from the research. Liz, the editor of a men's magazine, persuaded Jane to start a sex column under a false name. Jane's column quickly became a sensation, and before she knew it, she became one of the most talked about women in the country.
Although Jane was only trying to solve the emotional mystery at first, over time, she and Eddie also developed a good feeling for each other. Jane discovered that after all, the human heart - even a man's heart - is far more complex than pure instinct.
