When word comes through that two of the infamous Wallace brothers have been spotted in Indian Territory, Liberty Mercer - only the second woman ever to become a Deputy US Marshal - rides out to arrest them. But things don't go to plan, and Liberty finds herself left in the desert to die. Fortunately, rescue comes in the unlikely shape of a young girl named Clementina, on the run herself - from a stepmother who happens to be the matriarch of the Wallace gang...
