The Little family hunts all over the house for Margalo for days without finding her, and Stuart is heartbroken. They question Snowbell, who denies any knowledge of her whereabouts. Finally, Stuart realizes he will have to leave home and go out into the world to find her. He collects his things—including a strand of his mother’s hair to remember her by—and goes in search of his friend Doctor Carey, hoping for advice as to where to go to find Margalo.

Doctor Carey recommends that he go north, and he provides Stuart with a tiny model car. It has a gasoline engine and plenty of power, and it will take Stuart anywhere he wants to go. It even has a little button that will turn the car invisible. Stuart tests it out, but when he tries to make the car visible again, he accidentally puts it into gear. The invisible car races all over the office, banging into things until it runs out of gas.

When they are finally able to locate it again, the car has been badly battered, and Stuart’s spirits drop. He feels terrible for damaging Doctor Carey’s car. He is already homesick, and he is afraid he will never see Margalo again.