The Last Kids on Earth and the Monster Dimension

The highly anticipated ninth book in the #1 New York Times bestselling series! Jack Sullivan and his friends are back in their biggest, most mind-bending adventure yet. When a new threat emerges from another dimension, the team must face strange monsters, unexpected challenges, and shocking twists. As reality itself seems to shift, Jack and his friends will need all their courage, teamwork, and monster-fighting skills to save their world once again.