Charlie Chan in Behind That Curtain

This book is a murder mystery set in San Francisco. Charlie Chan the Chinese detective, on his way home to Honolulu, is persuaded to help with the investigation of the murder of a retired Scotland Yard commissioner. Sir Frederic has been re-investigating some old unsolved cases that have haunted him: a murder in London and the disappearance of a young woman in India. Charlie Chan suspects that one of these cases holds the clue to his murder.