Friday and Gannon are working day watch and must go to the hospital when a veteran police officer and his young partner are seriously wounded in a liquor store holdup where they deal with very different reactions of the wives.
An informant known as Black Ten turns Friday and Gannon onto a known burglar who is trying to sell an expensive ring that had been reported as stolen. They enlist the aid of a policewoman just out of the academy to help them undercover.
When a girl mysteriously disappears from school, Friday and Gannon try to find her and they find out that there are more questions than answers. One question is 'was she abducted by a man named Harper'.
Friday and Gannon are in the courtroom testifying in a case in which the probable cause for them to conduct a search of the suspect's car is in question. The probable cause is to be provided by a witness who is late arriving to court.
A man is eligible for parole from a Colorado prison. There's only one problem, there is an outstanding felony warrant on him in LA fourteen years ago. The Colorado authorities will not release him until they are informed on the disposition of the warrant. Friday and Gannon must re-investigate the case to see whether the case is prosecutable.
There have been a number of business burglaries the latest of which is a chemical supply firm. If properly combined, chemicals that were taken can be made into explosives such as TNT and gunpowder. One missing chemical will act as a catalyst in the explosives and Friday and Gannon must find the suspects before the thieves realize it.
An old Valdvillian finds 9 one thousand dollar bills on the street. He uses one to buy his friends drinks at a dive. The next morning a private detective claims that the money was lost by a big time gambler and pressures him to give it back. he does and discovers that the detective was a con man.
The police ask the press to publicize the M.O. of a woman who burglarizes elderly people in an effort to either catch her or scare her out of Los Angeles. She claims that an employment agency sent her out and when told that they never asked for help, she gains their confidence by doing things for them and steals valuables while doing it.
The detectives try to solve a series of residential burglaries. One victim reported that a jewelry case was taken containing $320. A stolen double-barrel shotgun was found at a pawn shop giving the detectives their first clue as to who may have burglarized one home.
It's Friday evening, Bill's wife is out of town and Joe has agreed to spend the weekend with him for some R & R, starting with a little pinochle with two neighbors. The next day the partners plan to "sleep in, watch the ball game on the tube, and have a dinner fit for kings. We're gonna live like sultans for two days, without harems, of course." What could go wrong with this plan?
When a man is arrested for possession of illegal pills, he provides information that may help him at trial. The information leads Friday and Gannon to a home used as a pill making factory and the detectives must try to locate the man running the factory.
Brought to their attention by a member of the Department of Animal Regulation, and with an okay from the Captain, Friday and Gannon investigate a rash of reports of lost dogs from a shopping center. Since only one lost dog had been previously reported from the same area, Friday and Gannon suspect criminal activity.
A forest ranger is brought in when checks and credit cards bearing other names than his own are found in his possession after he is stopped for a traffic violation. Even though he seems to be knowledgeable on the subject of forestry, his answers about the cards and checks lead Friday and Gannon to suspect he is a thief just posing as a ranger.
Friday arrests a fellow student after their night school class and incurs the wrath of Professor Grant, who expels him after a vote of the other students at their next meeting. Friday demands a chance to plead his case to the students before a second vote is taken. Grant says he must garner 2/3 of the votes to be reinstated.
Friday and Gannon are assigned to investigate Norm Bivins and Earl Malone, veteran homicide investigators accused of stealing $800 from a dead man. Agnes Emerson, who handled the man's business affairs, claims she gave Bivins and Malone his personal property, including $1000. They say the amount received was $200. Unfortunately, neither side can produce a receipt.
As Friday and Gannon investigate a series of robberies, a vindictive woman, Jean Sawyer, makes a pest of herself by calling headquarters repeatedly to accuse her husband of the thefts. The detectives investigate John Sawyer and find no evidence against him, but the man responsible for three of the robberies is found and arrested.