The Stupids

Stanley and Joan Stupid become convinced that a hidden conspiracy is stealing their garbage each week. They obsess over the idea and begin plotting to uncover the truth, setting their misadventures in motion.

Stanley follows the garbage truck to the city dump, hoping for clues about the conspiracy. At the dump he stumbles upon a far more dangerous revelation than he expected.

There Stanley encounters Colonel Neidermeyer, who is selling contraband weapons to terrorists. Neidermeyer mistakes Stanley for a secret agent and orders him assassinated, escalating the danger.

Neidermeyer and his men launch several assassination attempts on Stanley, but he survives and defeats some of his would-be killers. A car bomb nearly kills him, and Neidermeyer presumes he is dead.

Petunia and Buster believe their parents have been kidnapped and go to a Chinese restaurant to search for them. They eventually reunite with Joan, who explains her theory that the police have turned against them and are responsible for Stanley’s disappearance.

Back at home, Stanley recounts his last postal job involving letters marked \"return to sender\" and his firing before uncovering the idea of \"Mr. Sender.\" He shares his self-made conspiracy theory that ties all the bits together, including the Evil Mr. Sender.

The family uses the phone book to locate local museum curator Charles Sender and sets out to confront him. They hope he is the mastermind behind the mail and conspiracy.

Their pursuit leads to a television studio where Stanley appears on a talk show. Neidermeyer spots him and has him kidnapped, bringing him to an army base.

While held hostage on the army base, Stanley overhears the address of the warehouse used for the illegal arms deals, a clue that prompts the next move for the Stupids. The reveal confirms the scope of the plot and motivates their final push to stop Neidermeyer.

The Stupids escape and drive to the warehouse, where they confront Niedermeyer and his terrorist associates. Explosions draw in the police and several associates are arrested, but Neidermeyer escapes.

In a misguided moment of supposed heroism, Stanley offers what he thinks are steps for Sender to repent, but Neidermeyer interprets his words as road directions. The misunderstanding heightens the danger for the family.

The Stupids return home to find Neidermeyer waiting with a handgun. A deliveryman intervenes, knocking Neidermeyer out just in time, and the family ends with an outdoor barbecue celebrating their survival.