The adventure continues Part III of The Sixth Key Series is here Josie Ransom is back and ready for another adventure into the shadow world of magicians. Journey with her as she races to rescue her mother from the clutches of the evil Miss Wolf. The Infinite Backward is the biggest book so far with chases, near misses and breathless action. From the mountains of Colorado to the shores of Germany, the crew of Engine 17 has the same goal in both timelines: rescue Lizzy All will be revealed as the mysterious Mr. X finally reveals his sinister intentions. Family secrets, mystery and magic - it's all inside The Infinite Backward.