Old secrets can weigh heavy when you want to fly. Invited to a spectacular show by Slimwood's Stupendous Traveling Skycircus, Lily, Robert, and mechanical fox Malkin can't wait to jump aboard. But behind the daredevil acts of the bewitching bird-girl and other performers, something sinister lurks. And soon, the watchful ringmistress, Madame Lyon-Mane, reveals a deadly plan for Lily. Could the secrets of Lily's past hold their only chance at escape from this terrible trap?