Mrs Hart has been entered into a rose growing competition by Max, and her flower is chosen for the finals. At the same time, one of the main competitors a Greek organized crime figure is killed. They begin to investigate.

The Harts are on holiday in Acapulco, when they hear a senator has been assassinated. The assumption is the assassination is linked to bribery and corruption charges in the silver industry. The Harts find themselves investigating.

Due to an airline strike the Harts have to travel from Chicago to Los Angeles by train. They unwittingly get caught up in a murder plot involving other passengers.

A series of murders is linked to synthetic fur coat line that Jennifer Hart has agreed to model for. Can the Harts uncover the murderer before Jennifer becomes the next victim?

The Harts are interviewed by the FBI over an ex-employee who swindled money. Max gets caught up in the case when he is mistaken for Mr Hart and kidnapped.

Millionaire Dodsworth Nash has become infatuated with Mrs Hart. The only problem is Mr Hart stands in the way of Nash's plans to woo Mrs Hart. And Nash has made plans to remove the problem.

Hart recording artist Lorene Tyler (real life country singer Charly McClain) is beginning an international tour. Lorene's manager/husband Jesse, a jewel thief, has a costume made for her that sparkles with the stolen diamonds from a recent jewelry store robbery. After the outfit is loaned to Jennifer for a party, Jesse is determined to get it back at any price, even murder.

A man, who blames Jonathan for his sister's death, plants chemicals in the Harts' pool to blind him.

Max is kidnapped to force the Harts to throw a race in which their thoroughbred is running.

The Harts scuba dive too close to an embezzler's stash.

The Harts get involved with stamp thieves.

When Jonathan and Jennifer visit her father,he seems preoccupied about something. He doesn't tell them anything. Later when something happens, he reveals that after the war he and some other men were tasked with locating a Nazi and bringing him to trial. He now learns that the man's son is seeking vengeance and has taken out the men who helped him and now he's coming after him.

Jennifer has been brainwashed into stealing very expensive jewelry.

On vacation in Hawaii, Jennifer overhears a woman arranging for the murder of the woman's husband.

On a trip to an exclusive island French hotel, a friend of the Harts disappears. The staff at the hotel deny that their friend was ever a guest there.

Someone's trying to break up the Harts.

The Harts are in the thick of things when a Russian dancer seeks asylum in their home.

The Harts try to prove a friend is innocent after he's accused of his rich girlfriend's murder.

The distributors of the Harts new wine venture, are delivering - murder!

The Harts escape to their mountain cabin, and get involved in rescuing a young friend who's being framed for murder by the local sheriff.

The Harts get involved with tracking a double agent.

One of Jonathan's vice presidents dies, and leaves his family penniless; the Harts try to recover stolen vintage baseball cards that could be worth a fortune to the man's family.

Jennifer's life is at risk, after a rare coin dealer is killed during a robbery, and Jennifer ends up with the coin.

Jennifer appears to be at fault in a minor accident, but it was actually staged by the victim attempting insurance fraud. She and Jonathan are shocked when the victim dies due to complications, and then are sued by the grieving widow.