A coming of age story about James set primarily in late 80s Pittsburgh, Pennsylvania. James couldn't get a job anywhere else, so he works at the funpark "Adventureland", where he falls in love, meets legends, makes friends, enemies, life decisions, and pot-brownies. He also plans his future, if he can.
Greg Mottola was forced to create the video games seen in the arcade due to various video game publishers aversion to having their games featured in a movie that showed marijuana usage.
James Brennan, a recent comparative literature graduate from Oberlin College, is finishing up his planning for a summer European vacation before he heads off to study journalism at Columbia University. Unfortunately James' father gets a demotion and James is forced to move back to his hometown of Pittsburgh as well, his father is now unable to finacially support James' Europeon vacation or cover the cost of his education forcing him to look for a job for the first time.
After exhausting all other possible options, James is forced to work with his testicle-slapping childhood friend Frigo at the only place that will accept him: the local amusement park, "Adventureland," run by eccentric manager Bobby and his wife Paulette. Despite desiring the socially higher position of rides operator James is made to work in the lowly games section of the amusement park. In the games section of Adventureland James makes fast friends with the sarcastic and mono-toned Joel and "Em", a kind and intelligent girl who is dealing with a poor home life. James also meets the "legendary" Mike Connell. A maintenance worker with musical aspirations, Connell is famous around the park for having apparently once jammed with Lou Reed.
During James' first few days a customer attempts to cheat a game by lifting a child over the barrier to drop a ring on a bottle, when confronted on this the customers threaten James with a knife before Em steps in stating that "a giant ass panda isn't worth your life", following that day at work Em invites James to a party at her house. During the party James becomes romantically interested in Em, it is revealed after the party ends however that Em has a relationship with the married Connell. Following a date with Em, James confesses his deep romantic feelings towards her to the showboat rocker, who passes the information on to Em. Em tells James that she wants to take things slow in the relationship and not rush into anything.
Soon the park legend "Lisa P" comes back to work at Adventureland. Lisa P is notable purely for being the most attractive girl to work at Adventureland, she takes a shining to James and eventually asks him out on a date. James accepts the offer and goes to a romantic dinner with her; however when he returns home James is notified that Em had called to apologize for rejecting James by telling him to take things slowly. Acting on a previous conversation she and James had, he brings marijuana to Em so that they can make pot cookies. Following a pot-induced day at the amusement park, James accidentally reveals to a customer that a game is rigged, the customer, furious tries to push Em only to have James (in the spirit of Frigo) punch the customer in the balls and run. The customer chases James to the manager's office where Bobby comes out brandishing a baseball bat and threatening to use it. Em confesses to James that she doesn't want to lose him, much to chagrin of Joel who decides to quit. When James inquires into why his friend quit, Joel states that he doesn't think it's right for James to date Lisa P when he is clearly in love with Em.
James decides that Joel is correct and tells Em about his previous date with Lisa P. Em -- touched by his honesty -- sets off to break off her affair with Connell. Meanwhile Frigo, with the help of the parking attendant, discover the affair and tells James. James drives to Connell's house where he sees Em leaving after breaking off the whole deal. Surprised by the sudden confrontation, Em is unable to properly defend herself and explain her situation, leaving James furious. James tells Lisa P about the affair with the promise that she won't tell anyone, but she winds up telling her best friend Kelly. Soon enough the whole park knows about Em and Conell. Em, embarrassed by the situation, quits her job. James, now heartbroken ends up drinking his dad's hidden stash of alcohol in the car and drunkenly crashing the car. When his mother wakes him up from the car accident she informs him that he will have to pay for all the damages, essentially negating any money he made during his time at Adventureland. Following the retrieval of his last paycheck, James learns that Connell has not seen Em since she quit. Despite not having any money James heads to New York anyways and waits outside the apartment where he has heard that Em is living in. Em shows up and is shocked to see James, feeling like she has ruined everything between them, James states that he still has feelings for her, touched she lets him up into her apartment. Once in her apartment James takes off his wet clothes, as James and Em begin to kiss and undress.
Adventureland is notable for the poor marketing that was created around the film, which focused on the fact that the director was the same one who created Superbad. The studio pushed Adventureland as a similar teen comedy, while it's actually something considerably more serious and deep. Many reviewers commented that they felt that although Adventureland was a fantastic film, people were going to be disappointed when expecting a comedy as well as potentially spreading poor word of mouth about the film.