In 1882, Alfred Nichol, owner of the Nichol Railway Company, is building a railroad through the Canadian Rockies. He sends his irresponsible playboy son, James Nichol, to Hong Kong to check on the company's recruitment of Chinese laborers to work on the railroad's construction. One of the laborers James brings back is a orphan boy named Little Tiger. Unknown to James, Little Tiger is actually a young woman, who is masquerading as a boy to eke out a better living for herself. She is desperate to make it to Canada to find her missing father. Professionally, Little Tiger is tasked with being a tea boy to the other laborers on the construction crew, although she really wants to work on the more lucrative explosives team as, working at a firecracker factory in Hong Kong, she learned the finer details of explosives from a master. She also learns of some improprieties within the construction camp. Personally, Little Tiger falls in love with James, an unforbidden love even if she exposes her true identity to him because of their race differences. Ultimately, Little Tiger has a profound effect on her new Canadian friend.