The year is 1875, and twelve-year-old orphan Margret and her sister, Libby, are living with the kind Mrs. Fredriksen in her sod house in rural Littleton, Colorado. Margret would be happy to stay forever, but she knows that Libby, with her basic distrust of anyone other than Margret, will have them moving soon enough. Then a tornado sweeps through, bringing with it an injured horse. Immediately Margret lays claim to the horse, naming him Flynn, nursing him back to health, and teaching herself to ride. Now more than ever, Margret yearns for some stability in her life. Somehow, she's got to find a way to convince Libby to stay so she can make Flynn hers.