A half-day is declared at Fairfield High School after news breaks that student Erik Lowhouse was killed. While the rest of the student body copes with this sudden loss, freshman Wolfgang (Wolfy) has trouble recollecting him.
Enjoying their time off, Wolfy and his friend’s Toadstool (Toady) and Croner encounter two seniors, Steve and Taylor, who obviously have unfavorable ties to the freshmen. However, as they leave Steve invites Wolfy to join them. Without knowing what they’re doing or where they’re going, Wolfy is suddenly thrown in the middle of a fireworks war between them and two other kids.
Reassuring his friends that they didn’t do anything the night before, Wolfy keeps his oath of secrecy intact with the seniors. He is introduced to their friend Nate, who right away tries to intimidate him. Despite his unsettled approval, they continue letting Wolfy tag along in more of their pranks.
As they get to know each other better, several days pass by with them pranking more people. They begin to share more about their experiences and former escapades. After one evening, Steve and Nate show Wolfy a local bridge, where they share a story of Jake and Tiffany, a forbidden love.
Wolfy returns that night to his home to discover his sister, Ida, going through his computer. She agrees to get off his computer if he’ll make her a midnight snack. Discussing their night, Ida admits to going to the same party as Taylor and pokes fun at Wolfy’s adolescence.
The next day in Precalc, Taylor attempts to take advantage of a young substitute, however she keeps him in his place. Reactions flare when Taylor gets emotional over an accidental attendance call for Erik Lowhouse. His intentions are revealed as he gets consolation from an attractive classmate in the hallway.
Wolfy asks Taylor about his connections to Erik, having seen his display of sentiment, however he doesn’t give any details. Tensions rise when a high school jock and his girlfriend get cocky in conversation with the group of Steve, Taylor and Wolfy. After Wolfy feels inclined to leave the group, Steve informs him that Nate was wanting to tell him something in the auditorium. Before he has a chance to get there, Ida questions Wolfy as to why he was talking to Steve, but Wolfy keeps moving.
In the auditorium, Wolfy discovers Nate’s lair. In a weird kind of interrogation, Wolfy is shown more of Nate’s schematics and plans. After being informed of more, the two of them bike to Nate’s house after school. Nate shares with him his secretive prank book, which give them both laughs as to what the group of seniors have done in the past. The pranks range from compost piles to changing student records.
Back in school, Toady starts to get upset that Wolfy has been MIA from their LAN parties. Reassuring him that he’ll make it there tonight, he agrees to both that as well as a meeting at the parking lot with Nate at midnight. During the class, one of Erik Lowhouse’s letters is read as a memento to remembering him. Wolfy starts to get curious as he recognizes some of the names in the letter.
After Steve drops Wolfy off at his house, Ida is standing there waiting to talk to him. As they hash things out in the car, questions are raised as to what their past history consists of. That night, Wolfy shows little interest in the games he and his friends play, and after they both pass out, he sneaks out to meet the guys.
Now on their way to a prank, Wolfy uses the opportunity to raise questions regarding Erik Lowhouse, but little is answered. Nate then shows Wolfy their weapon of choice for the evening, a water balloon launcher. The target: the school jock and his girlfriend.
As the couple get cozy on the couch, the gang retreat to the backyard and start wailing water balloons at their house. As the moment heats up, the jock makes several attempts to yell threats for them to stop, however, they keep sending more and more. Sensing a pattern to his actions, Steve devises a quick plan to get him from the front of the house after Wolfy diverts him to the back. When the plan works better than expected, the jock is left soaking and starts running after them. Wolfy retreats back into the woods.
Wolfy returns to the spot where they left the car sometime later, only to find it was missing. As soon as he makes the discovery he is tackled to the ground by the jock and beaten several times. After he leaves, Wolfy lies there defeated and alone.
Several days later, Steve confronts Wolfy alone in a field. Steve tries to lighten the situation by joking, but Wolfy sits there silently. As Steve begins to leave, Wolfy finally questions their motives with his involvement, to which Steve has no wrongful intention. When Wolfy states that he knows about Erik Lowhouse, Steve makes a sly remark and leaves him unsettled.
In response, the two-part ways, never to speak again. As time passes, Wolfy graduates and learns from their time together. He appreciates what they had and takes it with him to college. Returning from fall break to the high school years later, he comes across a memorial for Erik Lowhouse. Reflecting back on their story together, he helps keep the legend alive.