Grown Ups 3 continues the comedic adventures of Lenny, Eric, Kurt, Marcus, and Rob as they reunite once again, this time for a summer road trip meant to celebrate their long-lasting friendship. After years of juggling work, marriage, and parenthood, the group decides they need a break from their chaotic lives. Lenny, who has become increasingly stressed by his high-energy children, proposes a week-long getaway far from their usual responsibilities. The others eagerly agree, believing that some time together will help them reconnect and relive the carefree spirit of their youth.

Their trip begins with excitement but quickly turns chaotic as the group discovers that they have very different ideas of what “relaxation” means. Eric insists on bringing a massive RV loaded with unnecessary gadgets, while Kurt wants to turn the trip into a fitness challenge. Marcus arrives without planning anything, and Rob brings along a series of bizarre “self-healing” activities he claims will help everyone spiritually. Their mismatched expectations create a stream of comedic arguments and misunderstandings that set the tone for the journey.

Along the way, the group stops at a lakeside town they visited decades earlier. Expecting a peaceful retreat, they instead discover that the town is now filled with younger adults who challenge them at every turn. The men quickly find themselves competing in beach games, sports contests, and even dance battles, desperate to prove that they still “have it” despite their age. The friendly competition becomes more intense than intended, pushing the group into hilarious and embarrassing situations that test their dignity and pride.

Meanwhile, the families back home begin to worry about the men’s reckless behavior. The wives exchange messages, suspecting that their husbands are getting into trouble again. Although the men claim the trip is purely for relaxation, their competitive antics tell a different story. As tensions rise within the group, old insecurities and personal frustrations start to surface. Lenny worries he’s becoming too old to be fun, Marcus feels aimless without responsibility, and Eric struggles with his fear of disappointing his family.

Things take a turn when the group accidentally damages property in the lakeside town, forcing them to work together to make things right. This mishap becomes a turning point, reminding them of the values that originally bonded them. Their efforts to fix their mistake bring heartfelt, humorous moments as they rediscover teamwork, humility, and the importance of friendship.

By the end of the trip, the men return home exhausted but closer than ever. Their misadventures help them appreciate their families and realize that growing older doesn’t mean losing joy—it simply means redefining it. Grown Ups 3 ends with the group planning their next gathering, proving that some friendships only get stronger with time.