After 8-year-old Mia loses her mother, her family moves to Grandma's Montana ranch. In the woods, Mia discovers a unicorn colt: a magical creature that brings luck to anyone who believes in it.

At only 8 years old, Mia has already had a tough life filled with hardship and bad luck. After the loss of her mother, she, her sister Emma, and their troubled father move to Grandma Rose's ranch in Middle-of-Nowhere, Montana. They're a broken family looking for a fresh start and needing a miracle. One day in the woods, Mia discovers a unicorn colt--a magical creature that brings luck to anyone who believes in it. Thinking she's found the perfect fix for her family's problems, Mia uses the unicorn to make life better, only to discover that the magic she yearned for was with her all along.