Cartoonist “Hoops” McCann works on a scholarship application to the Rhode Island School of Design (RISDY), before rushing off to attend his high school graduation ceremony. There, his friend, George Calamari, persuades Hoops to spend two weeks partying on Nantucket Island. George stops to pick up his sister, Squid, after school. She and her injured dog, Bosco, join George and Hoops for the trip to Nantucket. They stop for gas, and Hoops uses the restroom. A group of bikers check the stalls looking for a woman named Cassandra. As the lead biker demands money, Hoops finds Cassandra’s cash hidden in the towel dispenser, and throws the bills up in the air. He runs out, grabs Cassandra, and they jump into George’s car. George speeds to the ferry, which is leaving the dock. George’s car lands on the ferry deck, while the lead biker falls into the bay. During the ferry ride, Cassandra informs them that she is visiting her grandfather, Mr. Eldridge, who lives on the island. When they arrive, she suggests they might meet again. George introduces Hoops to his friends, fraternal twins Clay and Egg Stork. The group arrives at the home of George’s grandparents. Grandma fusses over Squid while George’s Uncle Frank listens to contest details on his radio. The crotchety man tells his nephew and Hoops to scram. George and Hoops go to Target Beach and meet another friend, Ack Ack “Acky” Raymond, who collects mortar shells for his father, General Raymond, the owner of the local guns and ammunition store. As they drive past a cemetery, Hoops notices Cassandra at her grandfather’s funeral. Meanwhile, at the Beckersted estate, Aguilla Beckersted asks his son, Teddy, if he is prepared to win this year’s regatta. Teddy has a new sailboat but the stakes are high. Old Man Beckersted, Teddy's wealthy grandfather, has vowed to disown Aguilla and Teddy, if the young man does not win the trophy. Aguilla wants to use his father’s resources to purchase the late Mr. Eldridge’s property and build condominiums. However, his plan will be foiled if Cassandra raises $3,000 to pay Eldridge’s back taxes. As Hoops walks with Cassandra on the beach, she explains her financial predicament. In addition, she worries that the friends her grandfather invited to live at the house will soon be homeless. Cassandra decides to sell some of her grandfather’s furniture to raise money. Hoops draws cartoons to cheer her up. Meanwhile, Uncle Frank is determined to phone in to the radio contest. He takes the phone and radio into the bathroom but slips on a bar of soap and shocks himself. On the beach, Hoops works at his drawings until George suggests that the Stork twins entertain his friend. As they chat, Teddy’s girl friend, Cookie Cambell, asks Hoops, Clay, and Egg to help her launch her boyfriend’s sailboat. Hoops declines Cookie’s offer to go sailing but agrees to go to the movies. Later, Hoops learns that Cassandra has raised some money selling her grandfather’s furniture. Cassandra invites him to the Dew Drop Inn to hear her play guitar. Hoops promises to be there, but has already made the movie date with Cookie. He tells his friends that he prefers to watch Cassandra perform, but Cookie shows up at the door, and he feels obligated to go to the movies with her. At the drive-in, Hoops buys snacks, and Teddy’s friend, Ty, notices that Hoops is with Cookie. Ty telephones his friend and reports that Cookie is on a date with Hoop. The news sends Teddy into a jealous rage. Egg Stork decides to crash a reception at the Beckersted estate and keep an eye on Teddy, but botches the mission by arriving too late. Cookie is bored at the movies, and suggests that they go to “the Point” and look at the moon. At the Point, General Raymond delivers a rousing speech to his Boy Scout troop about how their overnight retreat is a perfect opportunity to practice their rescue skills. Just then, Hoops slips and falls, and the scouts descend and wrap him in bandages like a mummy. The scouts chase after Cookie, but she runs away and Teddy picks her up in his car. George rescues Hoops, and they drive to the Dew Drop Inn, but it is closed. When Teddy arrives and threatens to beat Hoops, Cassandra steps in and challenges Teddy to compete against Hoops in a series of free-throw basketball shots. While Teddy makes every shot, Hoops misses all the baskets. Teddy is eager to rough up Hoops, but Cassandra sprays mace so that her new friends can escape. Hoops thanks her, and apologizes for missing her performance. Days later, Hoops sees Cassandra at the beach, and offers to use his animation skills to help her fundraise. He creates an animated advertisement for Cassandra’s performance, and shows it at the drive-in. He and his friends also hand out concert flyers in town. When Aguilla Beckersted realizes that Cassandra might raise enough money to save her grandfather’s property, he enlists Teddy to prevent her from performing. Hoops and his friends fight back by pouring barrels of lobsters into the Beckersted swimming pool. When Teddy goes for a swim, the lobsters attack him. Cassandra’s concert is a success, but when she shows up to pay the tax bill, the banker explains that he already sold the mortgage to Old Man Beckersted. Cassandra is ready to give up, but Acky Raymond suggests they enter a boat and win the regatta. The friends work to repair a shoddy boat, and Cassandra persuades Hoops to be captain. When the race starts, Aguilla Beckersted sabotages Hoops’ team by damaging their sail with an arrow from a cross bow. However, Hoops figures out a way to repair the damage. Aguilla aims to put a hole in Hoops’ craft, when a mechanical dolphin powered by Squid rams his boat and knocks him overboard. In the last lap, the racers retract the sails and engage the boats’ engines. Teddy leaves his father in the water and speeds toward the finish, unaware that the Egg twins installed the motor from his sports car on Hoops’ sailboat. Hoops and his friends speed to victory. Afterward, Hoops offers Teddy the trophy in exchange for the Eldridge house. However, Old Man Beckersted, impressed with the novice team’s effort, informs Cassandra that he is returning the Eldridge property to her. There will be no real estate development. Hoops and Cassandra celebrate and kiss.