Billy is bracing himself for the most boring summer ever, stuck in a remote lakeside cabin with no television, no video games, and no friends. The cabin belongs to the mysterious Dr. Libris, and it comes with a massive, locked bookcase and security cameras watching every corner. When Billy finally manages to open the bookcase and starts reading, something impossible happens. Every time he reads a story, he hears the clash of swords, the twang of arrows, and the roar of monsters coming from the small island in the middle of the lake. The characters from the books are actually coming to life! Soon, Billy is caught up in a wild, real-life adventure featuring Hercules, Robin Hood, and a host of other legendary figures. He must use his imagination and courage to navigate this magical mash-up and figure out the secret behind Dr. Libris's extraordinary island.