Nice guy John Plummer (Jason Lee) is engaged to ditsy Elaine Warner (Leslie Mann), and intends to use his life savings of $30,000 to put a down payment on a house because he does not want to accept money from her wealthy father, Mr. Warner (Dennis Farina), who is also John's employer and who already considers John unworthy of his daughter. Warner also has a mean dog named Rex who hates John and always agrees with his master. Simultaneously, his niece Noreen (Tammy Blanchard), daughter of John's "trailer-trash" sister, Patty (Megan Mullally), is accepted to Harvard University, but needs an additional $30,000 on top of her grants and scholarships in order to attend. Noreen shows her uncle John a videotape made many years ago, at which time he promised to pay for Noreen's college education when the time came if she were to work hard and be accepted to a university. John now has a moral and financial dilemmadisappoint his fiancée and prove her father right by showing that he cannot provide for Elaine, or disappoint his niece, sister, and her friends, who all look up to him, and take away his niece's only chance to escape from a life of lower-class poverty.John's best friend from high school, who was severely picked on and cried all the time, was an eccentric loser landscaper Walter "Duff" Duffy (Tom Green) tells John that one of his rich landscaping clients keeps large amounts of cash in an unlocked safe, and that no one is ever in the home on Sunday nights. Duff convinces John, who is bitterly opposed to the idea, that stealing from the homeowner would be okay, because no one would be hurt and the insurance company, which "deserve to be ripped off", would reimburse him. John reluctantly agrees, and he and Duff set out to steal the cash, but Duff runs off when lights come on in the home, leaving John staring down the barrel of the homeowner, Honorable Emmett Cook (Richard Jenkins)'s gun.Rather than being shot or turned over to the police, John instead finds himself forced at gunpoint to cross-dress and role-play the part of Cook's late wife as the two men lie in bed and "spoon". Eventually, after taking an incriminating photograph of John, one of many identical photos Cook keeps in an album while explaining to John that he is "not gay, I just miss my wife", Cook releases him. As he is leaving, Mr. Warner and his dog are riding by, and takes note of John's panicked behavior, believing that he has caught John in an affair which will be evidence he can use to persuade his daughter to call off the wedding.Further capers ensue as John and Duff attempt to rob a liquor store and later attempt to con a drug lord out of $30,000 by concocting a phony story about running an ecstasy ring. Meanwhile, a police detective (John C. McGinley) is on to John and Duff, but never has enough evidence to actually pin any of the crimes on them.Meanwhile, Mr. Warner breaks into the gun-toting Emmett Cook's house in order to get evidence against John, and once Cook catches him, he is also forced to "spoon". Before leaving, Warner finds the incriminating photo of John from the album in hand.Eventually, John is forced to confess everything to his fiancée, after her father confronts her with a photograph of John in drag with Cook. Not only is the fiancée not upset with John, but she now respects and admires him far more for the lengths he was willing to go to in order to provide for her, spare her feelings and send his niece to Harvard. The fiancée Elaine then confides in John that her wealthy father keeps a great deal of money at his business, and that it would be easy for them to steal it. John, Elaine, and Duff set out to rob the business in the night. Unfortunately, Mr. Warner had hid his dog Rex inside the vault. Rex attempts to attack Duff by biting him in the crotch but Rex is instead aroused and does not let go. Duff manages to get the lovestruck dog into a room, so he can try to break a window it make it look like a break in. Duff frantically tries to break a window (with Rex miserably watching while he tries to break out of the room in which he is trapped). The window will not break and Rex, yearning for Duff, finally escapes the room and jumps on top of Duff. Just as John and Elaine find the money, Mr. Warner finds them and tries to attack them but he is caught by the Detective who mistakes him for a burglar.John and Elaine escape to Duff's van but Duff is still being chased by Rex and has to jump inside the van but Rex follows them and finally has his way with Duff since there is nowhere else to run. The police arrive and the gang unsuccessfully tries to get away. They are all taken into custody by the detective and facing a series of charges including breaking and entering, animal cruelty, attempted vehicular manslaughter, (thanks to Duff selling him out), John feels like his goose is cooked, until the judge in charge of his arraignment turns out to be the gun-toting, Emmett Cook.Upon their mutual recognition, John writes, in his lawyer's notebook, a message to Cook and flashes it across the court, threatening to expose the judge's fetishupon reading the makeshift sign, Cook quickly dismisses all charges against John. Finally, Duff comes through as best he can and gives John his life savings, $1,000, which John bets on a longshot horse which wins and which paid 30 to 1. John and Elaine are married with Mr. Warner, Patty, Emmett Cook, and Duff among their wedding guests, Noreen goes off to college, and, in the final scene, John is left to ponder how loser Duff could possibly accumulate $1,000. The last scene shows Duff offering to "spoon" with Cook for $1,000.
Output: Question: What forces Duff to run away from the home they are robbing?, Answer: The lights came on