Quiz

The title of the movie refers to the drug Sherlock Holmes is abusing. He injects himself with a solution of seven percent cocaine and ninety-three percent saline solution.

While the book showed Dr. Sigmund Freud with a daughter, the child he had in real life, the movie showed him with a make-believe son, because Dr. Anna Freud threatened a lawsuit if she was included. Since her father was dead, she had no control over how he was portrayed.

The part of Mycroft Holmes was originally offered to Orson Welles.

Ironically, Dr. Sigmund Freud initially praised the use of cocaine, believing (like many others) that it had tremendous curative properties whilst also stimulating mental acuity and clarity of thought; he would often inject himself with the drug many times a day. He even introduced the drug to his friend Ernst Fleischl-Marxow with the best intentions. Marxow was a gifted physiologist and also a morphine addict, due to a painful injury he sustained that was only soothed by the opiate. Freud believed cocaine would help him to kick his morphine habit (which was a common belief at the time), but unfortunately it did not aid his friend, but rather added another problem, with which he had to deal, and may have been responsible for his early demise. Freud blamed himself for this, also noting with alarm his own extreme mood swings when under the influence of the drug, and determined to stop using it. Freud's paper on the deleterious effects of cocaine was the first proper assessment of its destructive side-effects, and won the physician his first widespread renown in the medical community. Freud became a strong opponent of narcotic use, even refusing pain-killers when, in later life, he became stricken with the cancer which eventually killed him in 1939.

The tennis match sequence was not a studio set but was shot at classic historical tennis courts at the Queen's Club in West Kensington, London.