Even though her family moved across the country for a "fresh start" after her little brother's death, eleven-year-old Zinnia Helinski still feels like she's stuck waiting for her new life to begin. Then she spots her new neighbor, Kris, climbing down the fire escape of their apartment building. He's wearing a black eye mask! And Spandex leggings. . . . And a blue body suit?

Soon Zinnia finds herself in a secret club for kids who want to be heroes. The Reality Shifters don't have superpowers, but they do have the power to make positive change in their neighborhoods. And a change is just what Zinnia is looking for!

At first, she feels invincible. Zinnia finally has friends and is on the kind of real-life adventures her little brother, Wally, would have loved. But when her teammates lose sight of their goals, Zinnia must find the balance between bravery and recklessness, and learn to be a hero without her cape.