To Catch a Thief.
Marge has scrimped and saved $100 to surprise Ed with a sports jacket that he wants. Ed accidentally finds the money, assumes that she has been holding out on the family finances and, in a huff, he takes the money and splurges on himself. Marge thinks that the money has been stolen and calls the police. Now that Ed knows the truth, he has to find a way to replace the money and keep Marge from knowing how he doubted her, all before amateur investigator Pertwee figures it out.