Field Trip: The kids are really looking forward to their field trip to the aquarium - especially when they remember the scary Lock Jaw from their last trip. But, when they get there, they see that Lock Jaw isn't really that scary. Arnold notices how neglected the old turtle looks, and returns later with Grandma to set it free.
Schoolyard tradition has it that on the first Monday of June each year, the fifth graders throw the fourth graders into trash cans. So, Arnold and Gerald try to make a run for it. As more people are thrown into trash cans and the fifth graders know all the routes, Arnold and Gerald find out eluding the fifth graders is harder than they thought.
Principal Wartz gives Sid a detention believeing he placed fake vomit so he could trip over, even though it wasn't Sid who put it there. As a result, Sid seeks revenge and reates 'Revenge Doll' of Wartz's face, like they do in tribes. He thinks he killed Wartz with the curse. Arnold thinks he's paranoid, even though there are a few clues hinting out that Wartz is dead.
Harold is invited to Rhonda's party, though he does not want to go as he thinks nobody will dance with him. While there, he dances with and befriends the female bully, Big Patty, who also had nobody to dance with. The two spend the next day together hanging out, much to the teasing of Stinky and Sid, who begin to tease him by saying he has a crush on her. They already tease Big Patty for being "big and dumb", which upsets Harold.
When a psychologist comes to PS 118, she notices Helga's behavior, so she calls Helga for a session. Reluctantly, she goes, and tells this psychologist about her life and how she behaved this way... Eventually, Helga ends up telling the psychologist her feelings about Arnold and gains a trust with Dr. Bliss.
When corrupt developer Schek threatens to buy the run-down urban neighborhood where a fourth grader Arnold lives, and now Arnold and his cool-as-ice best pal Gerald are on the biggest mission ever to save their neighborhood as they go up against a powerful industrialist who invades the city and buys everything in sight so he can knock it down and erect a huge "mall-plex." It's up to Arnold and Gerald to save their neighborhood before it's too late and they'll have to move somewhere else. But with the help of of a superhero and a mysterious deep-voiced stranger, Arnold and Gerald will need to recover a crucial document in order to save their beloved neighborhood at all costs.
In his urban legend, he tells the story of the ghost bride, and how she murdered her husband after he left her for her sister. Turns out she's buried in the cemetery near the gang's neighborhood. She comes back from the dead every anniversary of the murders. Arnold, Gerald, Eugene, Harold, and Stinky are scared twice by Helga and Curly, by them pretending to be the ghost of Cynthia Snell, the Ghost Bride.
When Arnold, the boarders and the Patakis go to the beach, a girl uses Arnold to win a sandcastle competition. Ernie gets buried in the sand. Miriam and Suzie start taking dancing lessons. Grandpa thinks he's stuck on an island. Oscar starts using a metal detector to find ""treasure."" Big Bob gets a bad sunburn. Helga tries to warn Arnold that he's just being used.
On the anniversary of his parent's disappearance, Arnold decides to give up hoping that they will ever return home. But while packing away their keepsakes in the attic, Arnold finds his father's old journal.
On the anniversary of his parent's disappearance, Arnold decides to give up hoping that they will ever return home. But while packing away their keepsakes in the attic, Arnold finds his father's old journal.