It all began the day before Hannah’s 12th birthday. Hannah was in the barn with her friends Sofia, Lisa and Sarah. While practising lassoing, the girls discovered a mysterious chest with the letters ….H ..C… on the lid. Hannah opened the chest with her penknife – and the friends were absolutely astonished. Inside the chest were photos of horses and a mysterious map. They thought they already knew every last inch of Lakeside: but what could be the meaning of the red X on the map between Lakeside Riding Stable and Peppertree Woods? The friends saddled their horses and galloped off – determined to get to the bottom of the mystery …