Basically "Before I Hang" is very simplistic and inconspicuous thriller story, but it is almost evidently brought to a much higher level solely thanks to the always-reliable performance and natural class of the iconic Boris Karloff. I wrote it before and I'll write it forevermore in my reviews: this man was simply amazing! With is moody voice, he could narrate the content of a phone book for all I care, because I would still hang on his lips. His charm and charisma make every movie atmospheric and his grimaces when he transforms from a seemingly gentle elderly person into a cold-blooded murderer (as masterfully demonstrated a couple of times in "Before I Hang") are utmost petrifying! Mr. Karloff truly was – and still is – horror personified! So, that concludes my ode to this brilliant actor, and on to the film itself. "Before I Hang" is actually another loose interpretation of the classic novel "Les Mains d'Orlac" by Maurice Renard. The novel first got turned into a film in 1924 already, in the German expressionist masterpiece "Orlacs Hände" starring Conrad Veidt, and several more times since, including two films starring Peter Lorre ("Mad Love", "The Beast with Five Fingers") and another one starring Christopher Lee in 1960 ("The Hands of Orlac"). Although the source material isn't specifically credited here, it's clear that Renard's novel also provides the basic plot idea. The movie opens with a beautiful and long Boris Karloff plea in court. He's physician Dr. John Garth, sentenced to death by hanging because he attempted to cure a man but failed. Awaiting his execution, Dr. Garth continues his experiments with the consent of the prison director and the help of the resident doctor, and he uses himself as guinea pig when he injects the serum into his own veins. Dr. Garth's execution gets overruled after all, but he begins to notice that the serum rejuvenates him. Unfortunately, however, he used the blood of a convicted murderer to finalize his serum and this bad blood is now slowly turning him into a merciless strangler as well. Classic Karloff material, in other words, with numerous fantastic monologues and a handful of eerie moments. Short (barely 60 minutes), intense and to the point; where would (mad) science be without Boris Karloff?