Krakatit (1948)
Krakatit is a 1948 Czechoslovak science fiction mystery film directed by Otakar Vávra, starring Karel Höger as a chemist who suffers from delirium and regret after inventing a powerful explosive. The film is based on Karel Čapek's novel with the same title, written in 1922. The name is derived from the volcano Krakatoa.
More at Wikipedia.