Harper asks Griffin to meet her at the portal after school, but, when Griffin gets home, he discovers his Grandfather has arrived for a visit.

Returning to the past, Griffin and Harper watch a murder unfold. The twins and Topher go to an unknowingly familiar someone for help.

Griffin Campbell and his family move to a new town and take ownership of an abandoned hotel in hopes of restoring it back to the lively vacation destination it once was.

Griffin and Harper learn the camp dance is coming up, and that is the day Savannah went missing! Later, Harper meets Jess, and learns her mom did go to camp and hated Savannah!

Ben is upset by the flurry of news reports marking the thirtieth anniversary of Savannah's disappearance, while Zoey and Wyatt see it as the perfect opportunity to finally capture her ghost on tape.

Griffin and Harper sneak back through the portal to find a search party looking for Savannah.

Griffin, stuck in the future, learns the ghost ruins their lives. Harper and Savannah try bringing him back to the present.

The twins arrive in the past and find Savannah. Griffin and Harper realize they need to go back to 1947 just as Ben makes the bunker off-limits.

The kids learn the ghost has been listening to them and is changing up his malevolent plans.

In 1947, Harper and Griffin meet Ruby. Sarah becomes increasingly freaked out by the ghost.

It’s time to get rid of the ghost.

The ghost will go, but will their future be saved?

Griffin and Harper realize they've time traveled to before Savannah's disappearance. When they go back again, they think they see Savannah getting taken into the woods.

A 12-year-old boy and a thrill-seeking classmate discover a secret portal that allows them to travel back in time and uncover clues about a mystery involving a girl who disappeared decades ago from a Louisiana town.

Griffin frantically searches for the missing crystal and helps a panicking Daisy to navigate her modern surroundings; meanwhile, Harper has a cryptic vision at the springs.

Once Griffin and Harper learn they can’t reopen the hatch to let Savannah in, they quickly go back through the portal.

Harper pretends to be Daisy to learn her family’s secrets, and Topher stumbles upon the hidden bunker.

When Sam can't get his Time Machine to work, Savannah vows to help him! Meanwhile, Griffin tells Daisy that he thinks Topher is hiding something and enlists her to find answers.

Harper and Savannah retrieve Griffin from the future. Sam and Griffin face the grimmest truth, Topher is in a coma in 2024. The twins and Topher almost catch Savannah’s “ghost.”

Griffin and Harper realize that Savannah could've traveled back in time.

Griffin and Harper successfully travel to the past, where they find Savannah working at The Tremont.

Griffin, Savannah and Harper find themselves face to face with Harper’s carbon copy, Daisy, and the Tremont ghost sends Harper and Griffin an important message.

When Daisy struggles at pretending to be Harper, Griffin searches for the crystal to swap them. After the Twins don't hear from Topher, they try to capture the ghost themselves.

Harper travels back in time to the date her father died in hopes of trying to change the outcome.

The Tremonts were duped by the Judge and have 48 hours to vacate their land. Meanwhile, when Griffin and Daisy rush towards the portal with the crystal, everything goes black!