20. The Seven-Per-Cent Solution (1976)
A pretty odd and atypical role for Duvall in which he was perhaps not well cast. He plays a Brit, Dr Watson, sidekick to Nicol Williamson’s legendary detective Sherlock Holmes in this non-canonical fan fiction tale (a genre that critic Gilbert Adair called “shlock Holmes”). Watson is convinced that Holmes is suffering cocaine-induced delusions (due to ingesting his “7% solution”), takes him to see Sigmund Freud – and they wind up solving a case.
