Sinner Take All (1936)

Members of a wealthy family start getting threatening letters, and it's not long before the threats turn into reality and family members start getting bumped off. The family lawyer is a former newspaper reporter, and since the family patriarch owns a newspaper, the lawyer uses his investigative experience and the newspaper's resources to dig into the family history to see if he can uncover the person behind the killings. The evidence he unearths seems to point to one person--his girlfriend.