Stuck at his grandmother’s house on a miserable, rainy Saturday, eight-year-old Jonathan is bored out of his mind—until he climbs into the attic. There, he finds a glowing, ornate box filled with a deck of magical cards. A handwritten note warns him to wait until he’s "ready," but curiosity gets the better of him. He pulls the first card—The Portal—and is instantly whisked away to Cardmere, a vibrant, magical world built entirely of enchanted playing cards.