The Chief assigns 86 and 99 to retrieve a deadly scientific theory from KAOS. The search takes the CONTROL agents to a TV studio, where they disguise themselves as dancers.
Max and 99 stumble on SIegfried's evil plot to destroy the U.S. potato crop while visiting 99's mother in Idaho.
Max is assigned to protect CONTROL Courier Busby during a plane ride, but Busby mysteriously disappears from the bathroom in mid-flight.
Thirty years earlier bank robbers Connie and Floyd met up with Sam Vittorio, who had robbed 192 banks. Now dying, Vittorio will only reveal the location of his hidden loot to his protégés, who look remarkably like Max and 99.
KAOS is using its League of Bald Headed Men to steal diamonds and smuggle them out of the country and fund their European payroll.
Each time Smart picks a best man for his upcoming wedding to Agent 99, the man meets with a mysterious accident. The Chief deducts that there must be a link between all of the accidents and KAOS because all of Max's prospects are fellow agents. To prevent further loss of manpower a t CONTROL, Hymie is appointed best man. KAOS then reveals it's true interest in Max's choice of best man - nearly to the extinction of CONTROL.
Max fills in at spy school for an afternoon and is forced to deal with two students whose grades are "alarming in disarming and failing in tailing." After a brief disarming session, he assigns 198 and 199 to 99 as she picks up wedding items. Unknown to Max, 99 is also on assignment and is really picking up the Gaul Formula. She spots the tails and believes them to be KAOS agents.
With an attempt to kidnap Admiral Hardgrade in the works, Max has him stay in his apartment.
The big day arrives for Smart and Agent 99, but almost without Smart as he is sidetracked by a bizarre case.
Smart wears a new blazer given to him by a Chinese merchant, Lin Chan. Smart, however, isn't aware he posses a weapon in the blazer, and is mystified as object disappear around him.
When Agent 99 is caught without dessert, she gratefully accepts chocolate mousse from her solicitious neighbor Naomi Farkas. Naomi and her husband Emil are secret KAOS agents who hope to photograph some papers the Chief has with him.
Max as an ensign and the Chief as a yeoman suddenly realize they'd better get off the ship if they are to thwart a KAOS plot.
The Smarts' honeymoon cruise ends when their sailboat blows up. They drift to an uncharted island, which soon proves to be owned by KAOS chief Seigfried.
Max must bring a scientist, Dr. Canyon, into the CONTROL camp. His problems multiply quickly; the invisible doctor turns out to be a pretty woman whose visibility returns just as Agent 99 enters their apartment.
The Chief believes KAOS has set up new communication system, which may be connected with a theatre group. Smart and 99 become thespians even though Smart's dramatic efforts are overly exuberant. The pair makes their debut, unaware that KAOS has discovered their identity and is planning a lethally realistic ending to the third act.
Agent 99's new job is at the Knights Trading Stamp Redemption Center. KAOS uses the center as a means of passing out a new secret weapon to their agents. KAOS agents Marco and Sonja run the center. The Chief has assigned several agents to find the secret weapon. The trail is cold, until 99 accidentally discovers that she is working for the other side.
Smart and 99 pose as a flamenco dancer and a seedy doctor to fool KAOS as both search for hidden gems in Mexico.
When the Smarts learn another center near a golf course has been earmarked for destruction by KAOS at a specific time, they plan to be on the course that day.
The Chief takes up computer dating and winds up dating a gorgeous young woman. The Chief's boss (unseen) orders Max and 99 to follow the Chief to make sure that this romance is not a security risk. 99 also thinks that the Chief should be dating someone more his age, like her mother. The young woman is actually the wife of Dr. Paponickolini, who is giving the Chief a secret formula for eternal youth. The Chief arrives at Max's apartment for a dinner date with 99's mom but instead KAOS shows up and kidnaps 99's mother, thinking she's the wife of Dr. Paonickolini.
The Chief uses a masked costume ball to switch King Charles for Max. Agent 99 soon has dificulty telling the two apart. Unfortunately, KAOS does not have the same problem uncovering the ruse.
99's confusion makes Max jealous and leads to marital coolness in the Smart household. KAOS has a more direct plan to solve the confusion: get rid of them both.
Dr. Erick Zharko and his assistant Bruce wire Max and 99 to a Dr. Frankenstein-like apparatus. Zharko figures that a jolt of his specially controlled electricity will shock Max and 99 into a five year sleep.
Wheelchair bound mastermind Leadside is caught in a robbery by Max and announces a three-part plan. Phase one, he will escape from Max. Phase two, he will destroy CONTROL. Phase three, he will kill Maxwell Smart. After Leadside follows through on Phases One and Two, Max holes up in his apartment, vowing "Leadside will only complete Phase Three over my dead body." This is one of my favorite episodes and Ronald Long is brilliant as Leadside. "My mother gave me Norman." The wheelchair in the back of the truck bit is still side-splittingly funny.
CONTROL corners KAOS Agent Klineschmidt in a house and attempts to take him alive. Before they can do that, he manages to shoot Max in the buttocks. Forced to stay at home, Max amuses himself by using binoculars to spy on the office building across the street. The office he's watching belongs to Otto Greer, who is a government contractor. Top secret papers have been disappearing from his office so the Chief assigns 99 to work undercover as secretary to Greer. Max keeps an eye on 99's progress and discovers too late that Greer is a KAOS agent planning to kill both of them.
Max is assigned to see Agent Kendall safely on a plane to Europe. However, Kendall mysteriously disappears from the airport after being paged. When Max takes the Chief to the airport to find out what happened, the Chief also disappears after being paged.
Smart and the Chief try all the standard escape methods and each time KAOS has Seigfried and his henchman, Starker, block them. The Chief realizes that there must be an informer in the camp and devises a plan to fool the informer.
