Eighth-grader Emma MacIntyre could use some good luck. The popular kids at school ignore her, the boy she likes is out of her league, and her best friend has been ditching her for the mean girls. Worst of all, her beloved Aunt Jenny died recently, leaving Emma and her single mom reeling with grief.

Then Emma receives a mysterious letter with no return address. The letter promises that ten lucky little things will happen to her over the next thirty days -- she just has to make a list of what she wants. When the things on her list start coming true, Emma races to understand what's happening. How does this lucky letter work? Who sent it? And what's going to happen when the thirty days are over?