While Jenkins discovers there's something wrong with the Library since it returned from the Void, the Librarians all find themselves drawn back together after having been off on their own for months, to solve the mystery of a massive storm that has parked itself over Manhattan. They soon discover the culprit in both cases is none other than Shakespeare's Prospero.

Prospero summons other fictionals in order to retrieve parts of his staff; the librarians find themselves pitted against Frankenstein's monster and Sherlock Holmes' nemesis Moriarty; Flynn and Baird have a disagreement.

While chasing one of the Library's missing artifacts, Flynn is kidnapped by a mysterious stranger with both amnesia and a collection of all the Library's missing artifacts. Soon all of them are in pursuit of the Staff of Zarathustra before it falls into the hands of Prospero.

The team has scattered, all living the ideal versions of their lives. Soon these “strangers” are drawn together to solve a supernatural mystery – the appearance of Ariel, the sprite bound to Prospero's service. Can the Librarians do what no other human has ever been able – turn their backs on their own ultimate happy endings?

The Librarians discover that Prospero's renewed magic is wreaking havoc with the technology of the world. He is recreating an idyllic forest utopia, whether we want one or not. In order to stop him, Flynn and Baird must travel back to 1611, while the rest of the team battles Prospero in the present. Little do they realize that they can only defeat Prospero in each time by finding a way to work together – separated by five centuries.