A very good thriller and surprisingly ahead of its time! Dr. Henryk Savaard, a scientist who he believe capable of bringing the dead back to life. His medical student volunteers as a subject to his life-threatening experiment, give his consent to be poisoned to death so he can be revived shortly after. Unfortunately he ends up being arrested and sentenced to hang before he can restore his student' life. So he come up with evil revenge plan before his hanging. Silly sci-fi story but Karloff showed his range and nailed his character incredibly well. The second third is too talky than the rest but never boring. Too bad the film ends with sudden conclusion.