Maycroft from 232nd

During summer vacation on a farm near Mattoon, Illinois Sarah and Hook Mattingly find clues in an old book that seem to reveal the location of a long-hidden treasure. Believing the clues to be part of a game created by their now deceased grandfather, Sarah and Hook set out with their Aunt Jenni to solve the riddle. By the time they realize the clues are real and are leading them into danger, it is far too late for them to stop.