When Ben accidentally is given the wrong change ($100 instead of a $10 bill) by a cashier at Toppers, he pockets the money. Ben is deep in thought about the $100 on the way home when his mom hits a darting cat in the road. At his insistence, they take the injured, scruffy cat to the vet and decide to go ahead with surgery, even though it is expensive.
Events unfold quickly. Ben confides to his friend Nate, just as the vet calls to announce that the surgery is successful. Ben argues with his mom about keeping the cat. Gwen, a waitress at Toppers, arrives. During supper, she tells the family that the cashier was fired for stealing money. Ben begins to regret his decision to pocket the money, but is afraid to tell his mother.
In the end, they bring home the cat. Ben decides to give the $100 bill to his mom for the surgery and reveals how he got the money. Reading level; 3rd grade and above and special education, 9 chapters , 9 illustrations by Liv Aanrud.