Have you ever waited for an elevator door to open and wondered, "What if...?" To every child, an opening door is an opportunity for wonder and excitement. For Claire Grant, one very special elevator does open on a realm of limitless adventure. And danger. Claire embarks on a campaign of discovery and magic, making friends and enemies in the lands where the stairs don't go. It's all great fun until her brother disappears into the mysterious worlds beyond the elevator doors and Claire must try and track him down. With the help of friends, Claire finds herself racing from one world to the next, trying desperately to find her brother and bring him home before it's too late