Assassin of Youth (1937) is an exploitation film directed by Elmer Clifton. It is a pre-WWII movie about the supposed ill effects of cannabis. The movie is often considered a clone of the much more famous Reefer Madness (sharing cast member Dorothy Short). The thriller reflects perfectly the anti-drug propaganda of its time.
(Summary from Wikipedia)
Copyright Info: This movie is in the public domain and is legally available for free on YouTube.