All is going well for Isaiah. He's the star quarterback on the verge of a football scholarship and one of the most popular kids at school. But when he helps throw a Halloween party at the Biddle House, he discovers an old camera in the basement and his life begins to spiral when he starts using it.

Isabella feels invisible. She doesn't have many friends at school and spends most of her time trolling her classmates on social media under a fake account. At the Halloween party, Isabella discovers a mask in the basement of the house. When she puts it on, the mask gives her a newfound confidence, but things take a turn when the mask starts to control her life.

James wants desperately for people to like him. At the Halloween party, James finds himself in a time loop reliving the same night, but he ultimately breaks free hand-in-hand with his crush. This fairytale quickly turns into a nightmare.

Lucas aspires to be a daredevil, just like his dad used to be, but his reckless stunts make people nervous and they often result in broken bones and damaged property. At the Halloween party, he finds some worms at the Biddle House and he takes them home with him. He soon learns these aren't just regular worms.

Mr. Bratt gives Margot an old scrapbook he found in the basement of the Biddle House. As she flips through the pages, she's sent on an unexpected journey to 1993 when her mom was a student at Port Lawrence High. As Margot delves deeper into the book, she learns secrets that have terrifying consequences.

Mr. Bratt tells the teens about Harold Biddle and the history of the house. In this decades-spanning story, the teens get closer to discovering the truth about what’s haunting Port Lawrence and who might be responsible for it.

The group works together to find a way to escape their new reality. As they search for a way to get back to the real world, they make new discoveries about Harold Biddle. Meanwhile, Nora takes matters into her own hands and treks to her remote cabin in the mountains to keep an old horror at bay.

Back in the real world, the teens rush to Nora's cabin and find themselves on a dangerous journey to try and save Nora from an old friend.

As the teens get back from their Seattle trip, they quickly realize their loved ones and all of Port Lawrence are in grave danger. A new evil has taken over the town and they need to band together to save it.