The gang emerge from a cave to find themselves in an alternate reality… where Uncle Charlie never went missing! But it soon becomes clear that their presence is affecting the island and in order to save it, they must return to their own reality.

Taylor and her friends must save the island from an ancient piece of glass that is wiping everyone's memories. But will they even be able to remember there is an island to save? And more importantly, will they remember Lila's birthday?