In 1978, a close-knit group of friends celebrated their victory in the junior high basketball championship under the guidance of their beloved coach, Buzzer (Blake Clark). He advised them to live their lives with the same passion and teamwork they displayed on the court.
Fast forward 30 years, and we find Lenny Feder (Adam Sandler), a high-profile Hollywood talent agent married to Roxanne (Salma Hayek), a talented fashion designer. They have three children: the overly pampered Greg, Keith, and their daughter Becky. Meanwhile, Eric Lamonsoff (Kevin James), a co-owner of a lawn furniture business, enjoys family life with his wife Sally (played by Maria Bello), raising their daughter Donna and son Bean, who is still breastfeeding at the age of four. Kurt McKenzie (portrayed by Chris Rock) is a stay-at-home dad married to the family’s breadwinner Deanne (Maya Rudolph), balancing life with their children, Andre and Charlotte, while Deanne is also expecting a third child. The mothers in their lives, notably Deanne's mother Ronzoni, frequently chide Kurt for not contributing enough to the household. Additionally, there's Rob Hilliard (Rob Schneider), a pacifist vegan, who's thrice divorced but currently married to Gloria (Joyce Van Patten), who is significantly older than him. Marcus Higgins (David Spade) has embraced the life of a carefree single man.
The group comes together again for Buzzer's funeral, a poignant occasion that draws memories of their youth. Lenny organizes a getaway to a lake house for the 4th of July weekend, although he must leave early for Roxanne's fashion show in Milan. At the lake house, Lenny encounters his long-time rival, Dickie Bailey (Colin Quinn), who is irked by Lenny's past gameplay and dares him to a rematch, a challenge Lenny delicately sidesteps.
During their gathering, they plan to honor their late coach by spreading his ashes. Lenny's commitment to family is put to the test when he reveals to Roxanne that he can’t be present due to her fashion commitments, igniting tension between them. However, as they come together in the morning to fulfill their promise to Buzzer, Rob's daughters Jasmine and Amber arrive — their stunning looks leaving everyone questioning Rob's parenting skills, especially with his daughter Bridget, who strikingly resembles him.
As the weekend progresses, Lenny's children gradually blend in with the others, creating bonds and even constructing cup phones around the house for fun. Upon learning that Roxanne decides to stay, the group's dynamics shift positively. Emphasizing the joy and levity, Bean learns how to drink from a carton while Marcus flirts with Rob's daughters. Their fun takes an unexpected turn when they run into Dickie again, this time accompanied by his friend Wiley (Steve Buscemi), who later winds up in the hospital after a comical mishap on a zip line.
Conflicts arise as Deanne becomes suspicious of Kurt's newfound closeness to Rita, Lenny's nanny, leading to a pivotal night where the adults let loose and dance. The next morning, Rob suspects that Marcus may have been more than just friendly with either Jasmine or Amber, while Roxanne uncovers that Lenny canceled their Milan trip without her knowing. Amidst the chaos, Lenny asserts that their time at the lake house was essential for their children's growth, even if it meant risking Roxanne's approval.
In an open discussion, Deanne confronts Kurt about his alleged flirtation, prompting an honest exchange where Kurt admits to enjoying genuine conversations he feels are lacking in his marriage. Meanwhile, Eric reveals his job loss, feeling embarrassed about not being a success, which leads Lenny to consider investing in his friend's future. Over a spirited 4th of July barbecue, the group finds themselves once more challenged by Dickie and his friends to a rematch of that long-ago basketball game. With excitement in the air, even as their physical prowess has waned, they rally together, motivated by the legacy of their coach.
The game intensifies, ultimately culminating in a showdown between Lenny and Dickie. When faced with the opportunity to win, Lenny surprises everyone by deliberately missing the shot to give Dickie a taste of victory, embodying the spirit of camaraderie that Buzzer emphasized all those years ago. The group learns to embrace their loss, savoring the memories and connections they've built together.
