Ohne Dich wird es Nacht(1956)

Dr. Kessler, a lawyer in poor health, actually just wanted to take a dose of morphine to get fit for his court appearance. But the necessity turns into an addiction. It is only when Kessler falls in love that he goes into rehab. However, it is not long before temptation takes hold of him again and the morphine threatens to destroy Kessler's life and his new love for good.