The film's premise is that Sherlock Holmes is a fictional character created by Dr. John Watson (Ben Kingsley) to enable him to solve crimes incognito. To satisfy public demand to see Holmes in person, he hires alcoholic unemployed actor Reginald Kincaid (Michael Caine) to play him. But when "Holmes" begins hogging the spotlight, a jealous Watson fires him, only to have to call him back when the British Government wants Holmes and no one else to solve a mystery involving stolen Bank of England £5 banknote printing plates and a missing printing supervisor, Peter Giles.
Inspector Lestrade (Jeffrey Jones) is jealous of Holmes' apparent sleuthing skills, and takes every opportunity to spy on Holmes and Watson and to steal their ideas. Just when Watson and "Holmes" discover that Professor Moriarty is the mastermind behind the scheme, Watson is apparently killed in an attempt to capture Moriarty, forcing "Holmes" to solve the case on his own.
|Michael Caine||Sherlock Holmes (Reginald Kincaid)|
|Ben Kingsley||Dr. John Watson|
|Jeffrey Jones||Inspector George Lestrade|
|Lysette Anthony||Lesley Giles (Fake)|
|Paul Freeman||Professor James Moriarty|
|Pat Keen||Mrs. Hudson|
|Nigel Davenport||Lord Smithwick|
|Tim Killick||Sebastian Moran|
|Peter Cook||Norman Greenhough|
|John Warner||Peter Giles|
|Matthew Sim||Lesley Giles (Real)|
|Harold Innocent||Lord Mayor Gerald Fitzwalter Johnson|
|George Sweeney||John Clay|