On the first morning of summer, Pip ran down to the beach and almost tripped over her dog Biscuit. He had a green bottle in his jaws, washed up between two rocks. Pip pried it open. Inside was a paper torn down the middle: half a coastline in faded blue ink, and one word left at the rip. It said HARBOR.

Pip knew the old harbor. It was a twenty-minute ride up the coast road. She grabbed her bike from the porch, tucked the map in her pocket, and whistled. "Come on, Biscuit. The other half of this map has to be somewhere." Biscuit barked and chased after her wheels.

At the harbor, Pip found a row of crooked old boathouses. On the wall of the last one hung a faded paper that looked exactly like her map's missing half. But it sat behind a cracked glass case, locked shut with a rusty padlock.

The padlock wouldn't budge. But Biscuit barked at a gap under the boathouse door. Pip squeezed inside and found a journal open on a workbench. The last page read: "The second half hangs above the door." She looked up, and there it was, taped to the beam. She tugged it down and matched the two halves at last.