1863, in the midst of a convoy heading West on its way to a better life, Martha Jane’s father gets hurt. It is she who must drive the family wagon and take care of the horses. Learning is tough and yet Martha Jane has never felt so free. And since it’s more practical for riding horses, she doesn’t hesitate to slip in trousers. It is too much boldness for Abraham, the leader of the convoy. Accused of theft, Martha has to run away. Dressed as a boy, searching for the evidence of her innocence, she discovers a world in construction where her original personality will assert itself. An adventure full of dangers and rich in encounters that will, step by step, reveal the mythical Calamity Jane.