It features the Sherlock Holmes and Dr. John Watson characters created by Sir Arthur Conan Doyle, who are embroiled in the investigation surrounding the real-life 1888 Whitechapel murders committed by "Jack the Ripper".

After the Metropolitan Police fail to apprehend the serial killer Jack the Ripper, Sherlock Holmes is approached to investigate the recent murders of prostitutes in the Whitechapel district of London.

Furthermore, Inspector Foxborough, the policeman who is in charge of the case, is in fact the secret leader of the radicals, a political movement waiting for the British government to fall because of its inability to solve the Whitechapel murders.

"[5] James Mason's Watson is also a departure from previous incarnations; although he may appear at first to resemble the bumbling Nigel Bruce version of the character, he soon shows his level head and scientific and medical training to be as valuable assets as they were in the original stories.

[5] The supporting cast includes Donald Sutherland, Susan Clark, John Gielgud, Anthony Quayle, David Hemmings and Geneviève Bujold.

[3] Vincent Canby of The New York Times called the film "a good deal of uncomplicated fun, not in a class with Nicholas Meyer's The Seven Percent Solution, but certainly miles ahead of many other current movies that masquerade as popular entertainment".

"[12] Gene Siskel of the Chicago Tribune gave the film two-and-a-half stars out of four and wrote that its "biggest problem is its script, which runs on for a full 120 minutes with no place to go.

"[13] Kevin Thomas of the Los Angeles Times wrote, "Unfortunately, under Bob Clark's uninspired, plodding direction, Hopkins' elaborations make for a slow and ponderous film, despite a starry cast and some scary moments.

"[15] Gary Arnold of The Washington Post stated, "While never as playful or ingenious as Nicholas Meyer's screenplay for 'The Seven Per-Cent Solution,' Hopkins' mystery is crisp and chilling right up to the denouement.

Christopher Plummer and James Mason seize their roles like a couple of happy musicians handed prize antique instruments: their duets are by turns droll, lyric and touching.