Charlie Cantilini (Jennifer Lopez) is a temp/dog walker/yoga instructor and aspiring fashion designer from Venice Beach, California, who meets doctor Kevin Fields (Michael Vartan). At first, she thinks he's gay because of a lie his vindictive ex-girlfriend Fiona (Monet Mazur) told her. But then Kevin asks her out and she believes that she has finally found the right man.
Things start to sour when Kevin introduces Charlie to his mother, Viola (Jane Fonda), a former newscaster who has recently been replaced by a younger woman, causing her to have a meltdown and attack a guest on-air. Loathing Charlie immediately, Viola becomes more distraught when Kevin proposes to Charlie; she fears she'll lose her son the same way she lost her career. She sets out to ruin Kevin and Charlie's relationship, enlisting the help of her loyal assistant Ruby (Wanda Sykes). The two try everything possible to drive Charlie away, even tricking her into eating nuts, which triggers a severe allergic reaction.