Mouse Hunt (film) - Plot

Plot

After Lars (Lee Evans) and Ernie’s (Nathan Lane) string manufacturer father Rudolf (William Hickey) dies, they go over his will in his now-outdated factory, where they find out that he left them a handful of personal items, one of them being a deed to a debt-ridden mansion.

Representatives from a company called Zeppco International offer to buy the factory from Lars after being turned down several times by Rudolf, but he refuses their offer after remembering his father giving him and Ernie his lucky piece of string and made a promise to him to never sell the factory. He is later kicked out of his house by his self-centered, money-hungry wife April (Vicki Lewis) after she discovers this. Meanwhile, Ernie serves Mayor McKrinkle (Cliff Emmich) at his restaurant Chez Ernie, but the mayor soon suffers a heart attack after accidentally consuming a cockroach — which was hiding in a cigar box Ernie received in his father's will and took to the restaurant with him — found in his dish. As a result, Ernie loses his restaurant and home.

He then reconciles with Lars at a diner and they both decide to investigate the mansion, since they do not have anywhere else to live. While sleeping there, they find blueprints of the mansion, which show that is built in 1876 by the famous architect Charles Lyle LaRue. As it was the last house built by him and until now considered a mere rumour — LaRue having been committed to an asylum shortly after finishing it — the mansion is dubbed “The Missing LaRue”. Alexander Falko (Maury Chaykin), a LaRue item collector, attempts to make a $1.2 million offer on the house; Ernie, however, convinces Lars that they will make a lot of money if they restore and auction the mansion. However, they soon discover that they only have two days left to pay the house's $1,200 mortgage before the bank forecloses on it.

As the brothers begin renovating the mansion, they realize that the house already has an occupant, in the form of a highly intelligent mouse. Fearing an incident similar to the cockroach incident, Ernie and Lars decide to get rid of the mouse. They begin a series of increasingly aggressive and comical attempts to kill the mouse, all of which fail when the mouse sabotages their efforts, also causing comic harm to the brothers after each failure. In one attempt, Ernie and Lars go to an animal shelter where they adopt a mentally-ill cat named Catzilla. However, Catzilla is subdued by the mouse after it corners him in a dumbwaiter and gnaws the rope, causing Catzilla to fall and end up trapped at the very bottom of the shaft, where he presumably eventually dies of his injuries. The brothers then hire an eccentric exterminator, Mr. Caesar (Christopher Walken) to kill the mouse. This attempt also fails, when Caesar ultimately falls victim to a master-trap set by the mouse and is driven insane with rage at his first ever failure.

Lars reconciles with April when she hears about the upcoming auction from the brothers' lawyer (Although he is unaware of the reason for her new interest). Ernie, meanwhile, discovers the Zeppco documents in the factory's office and contacts the same representatives who Lars turned down to meet with them in the town square and discuss selling the factory, but he flirts with two Belgian hair models, Ingrid and Hilde, and loses his hat. He ends up struck by a bus while retrieving it, ironically just as the representatives arrive, but his injuries are minor and he is allowed to leave when Lars picks him up.

The brothers return home as Caesar is taken away by paramedics, and another battle with the mouse begins, which results in Ernie being blasted out of the chimney and into a frozen lake in a ball of fire. Completely berserk, Ernie grabs a shotgun and fires at the mouse, missing each time and causing the floor to collapse by accidentally shooting a bug bomb previously dropped by Caesar. Zeppco, by answering machine, declines their offer to buy the company, and the brothers argue about betrayal; Ernie is angry that Lars turned down Zeppco's first offer without consulting him first, while Lars is angered that Ernie was willing to sell the factory without telling him. The argument eventually shifts towards the subject of their father, who always favoured Lars over Ernie because Lars was the elder brother, and Ernie's bitterness about never winning their father's approval before his death. At the height of their arguments, Lars throws an orange at Ernie, who dodges, and it hits the mouse, knocking it unconscious. The brothers attempt to finish it off with a shovel, but cannot bring themselves to harm the defenseless creature. Instead, they put the mouse in a box and mail the box to Fidel Castro in Cuba. Elated at being rid of the mouse, the brothers quickly reconcile and work together to repair the house and prepare it for the auction after April pays the mortgage.

Unfortunately, during the auction, Lars discovers the mouse’s parcel, which was returned due to insufficient postage, with a hole chewed through it. As the auction begins, Lars and Ernie once more try to kill the mouse. In one, final, desperate attempt, they feed a hose into a hole in a wall to try and flush the mouse out. This backfires horribly when the water fills the spaces between the walls of the house just as the auctioner bids $25 million. Those present for the auction are washed outside when the walls around them collapse, and despite Ernie's attempts to convince them to stay, they leave as the house collapses, including April, who leaves Lars and goes off with a particularly rich bidder from the auction. The brothers' only consolation is the fact that the mouse is most likely finally dead.

The brothers return to the factory and sleep there. However, the seemingly indestructible mouse has followed them and manages to make a ball of string cheese by dropping a slab of cheese into the wax receptacle. Ernie and Lars end their war with the mouse, taking its suggestion for the future of the factory. The dying factory becomes a success as it is now manufacturing string cheese, with Ernie and the mouse working together to create new blends — Ernie speculating on the mouse becoming their spokesman as it works as a taste consultant — and the brothers apparently forming romantic relationships with Ingrid and Hilde.

The closing scene shows the portrait of Rudolf Smuntz beaming — after previously displaying various grim expressions throughout the movie, his lucky piece of string framed and hung beside the portrait, with the quotation "A world without string is chaos."