Sergeant Blake of the Northwest Mounted Police is sent to the border to break up a ring of smugglers who are bringing illegal Chinese immigrants into Canada. The ring is led by Ah Ming, a "half-breed" who goes by the name of Dr. Lawler. When Blake encounters Lawler, he is experimenting on a white mouse.
Lewis Stone
Wallace Beery
Ethel Grey Terry
Willard Louis
Bessie Wong
