The Secrets of Wu Sin (1932)

Newspaper editor Jim Manning prevents a destitute young writer from committing suicide and gives her a job on his paper. When Manning gives a hot story assignment to reporter Eddie Morgan, the girl, Mona Gould, decides to investigate the story herself. At issue is the smuggling of illegal Chinese workers into America by ship. Mona discovers that a trading impresario, Wu Sin, is involved, as is a very wealthy man whose daughter is engaged to Jim Manning. Wu Sin blackmails a young man, Charlie San, into murdering Mona when he learns of her discoveries. But Charlie, whose girlfriend Miao Lin is Mona's friend, is a good man and his heart is not in the effort. Can Charlie carry out his orders, and will Mona expose the criminals before he does?