Daniel Hillard likes to entertain children. His job is providing voices for cartoons, but when he disagrees with the image that the studio wants to convey to children, he's fired. It is also his son's birthday and feeling down and wanting to do something special for him, he throws a wild children's party. His wife, Miranda, comes home and finds the house in shambles. After everything settles, she tells him that they are on different paths and thinks that they should get divorced. Because he's unemployed the judge feels that it's best if he gets his life in order first, so he allows him to see his children just one day a week. But he can't bear to be away from them for so long, so when Miranda decides to hire a nanny, he alters the ad, answers it himself, and pretends to be Mrs. Doubtfire. Donning a disguise, he becomes the new nanny.