Plot
Bob and Cindy Russell relocate from Indianapolis to the Chicago suburbs with their three children: rebellious teenager Tia, talkative eight-year-old Miles, and six-year-old Maizy. Tia resents the move and her relationship with her mother is fraught. When Cindy's father suffers a heart attack, Bob and Cindy must travel back to Indianapolis on short notice. Unable to find a suitable babysitter, they reluctantly leave the children in the care of Bob's irresponsible brother, Buck.
Buck is an unemployed bachelor who makes a living by betting on horse racing and indulges in heavy drinking and smoking. His long-term girlfriend, Chanice, wants to settle down and start a family, but Buck wants to retain his freedom and avoid responsibility. Despite never having met Miles and Maizy, Buck quickly bonds with them through his humor and unconventional approach to caregiving, while Tia remains openly hostile and embarrassed by his behavior.
As Buck adjusts to suburban life, he struggles with domestic responsibilities but makes genuine efforts to care for the children. He takes them bowling, defends Maizy from her strict school assistant principal, and throws Miles an improvised birthday party, driving off an unreliable clown who arrives late and intoxicated. He also grows suspicious of Tia's boyfriend, Bug, believing he is interested only in having sex with her.
Tensions escalate when Buck interferes with Tia's plans to spend time with Bug. In retaliation, Tia falsely tells Chanice that Buck is having an affair with their flirtatious neighbor, Marcy. When Chanice later sees Buck dancing awkwardly with Marcy, she believes the accusation and ends their relationship. The incident prompts Buck to reflect that the carefree lifestyle others once envied is no longer admired.
When Tia sneaks out, Buck faces a dilemma: attend a high-stakes horse race that could secure his financial future or search for Tia. Worried, he asks Chanice to watch Miles and Maizy while he traces Tia and Bug to a party. There, Buck discovers Bug forcing himself on another girl and binds and gags him, locking him in the trunk of his car. He later finds Tia walking home, upset, and she admits Buck was right about Bug. She and Buck reconcile, with Buck admitting both his failings and his love for Tia. Buck then forces Bug to apologize to Tia before releasing him.
Later, Tia confesses to Chanice that she lied about the alleged affair, telling her that Buck has changed and urging her to give him another chance. Buck and Chanice reconcile, and Buck agrees to take a steady job at her auto shop. When Bob and Cindy return home following Cindy's father's recovery, they find their family dynamics improved. Tia begins repairing her relationship with her mother, while Buck departs on good terms, inviting Tia to visit him in the city before they exchange an affectionate goodbye.