While trapped in the future, Griffin learns that the ghost is ruining their lives; Harper and Savannah try bringing Griffin back to the present.

Harper and Savannah retrieve Griffin from the future; Sam and Griffin gets the truth; Topher is in a coma in 2024; the twins and Topher almost catch Savannah's ghost.

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.

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

It's time to get rid of the ghost.

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