It's a good news/bad news situation for Malloy. The good news is that it's his birthday. The bad news is that he forgot to renew his drivers license and must now let Reed drive Adam-12, something he was always nervous about. Also, during this day, the officers must deal with an unusual bank robbery, an abandoned baby, a woman who murdered her husband on their wedding anniversary and a drug dealer who uses an ice cream truck to sell marijuana and other drugs.

Malloy and Reed are called to a riding stable run by retired actor Slim Berkeley. The owner is careless about trusting people and has $100 and a gold belt buckle stolen. By instinct due to a record in New York his young assistant runs but when searched nothing is found. A call to a phone booth where the man inside is being attacked by another man leads to a drug arrest and sore jaw for Reed. Reed spots a robbery at a drive-in resulting in a shoot-out and capture of the robber. An illegally parked car with a woman who refuses to move the car leads to a second shoot out with two men robbing a liquor store. A complaint is filed by a jewelery salesman. His new convertible is poured full of concrete by the husband of his client in front of the client's house (the concrete had time to completely harden). When Slim reports a second robbery of his clients money, the mother of one the clients comes forward to say her daughter has a history of theft and she returns the belt buckle.