A ghost, time travel, and unusual friendships await Kean in Walhachin. Kean feels displaced at his home in Seattle since his mother recently re-married and has chosen to spend the summer in the small desert town with his aunt and younger cousin. Not long after arriving, he regrets his decision. There is no one his age. The town is too small for public amenities. Then everything changes when he uncorks an old soda bottle that was made in Walhachin eighty years prior. He becomes embroiled in an adventure to try and help a ghost retrieve a much-needed item from the past. In his quest to help the ghost he discovers the town's spirited history and develops unusual friendships with an old man in the present and a young boy in the past.