After their first year of college, Jim and his friends reunite for a summer of fun at a beach house. They throw parties, get jobs, and engage in various humorous and sexual escapades. Jim seeks advice on improving his sexual skills, Oz deals with a long-distance relationship, Finch explores Tantra, and Matt, Stifler's brother, gets into a hilarious misunderstanding with two women. In the end, they all learn valuable lessons about love and friendship.

Jim, Michelle, Stifler, and their friends gather in Michigan for their high school reunion. As they navigate through various comedic and awkward situations, they rediscover friendship and the importance of relationships.

Jim and Michelle are getting married, but chaos ensues when their families and friends come together. Stifler, an unwanted guest, causes trouble throughout the wedding preparations. Jim must navigate through various mishaps and obstacles in order to ensure the success of his wedding. Meanwhile, Stifler has his own challenges - trying to impress Michelle's sister, avoid revealing his true self, and organizing an epic bachelor party. Ultimately, Jim and Michelle's love prevails, and they have a memorable wedding ceremony and reception.

Four teenage boys, Kevin, Oz, Jim, and Finch, enter a pact to lose their virginity by prom night. They each face challenges and obstacles as they navigate through awkward sexual encounters and relationships. Along the way, they discover the importance of friendship, love, and acceptance.