It was a box-office success, grossing over $17 million, but received mixed reviews from critics, with several deriding it as an exploitation film that featured a number of inaccuracies in its depiction of the actual crimes and of DeSalvo.

After three murders of elderly women, the victims being strangled and penetrated with foreign objects, the Boston police conclude that they have a serial killer to catch.

As the murders stretch over several police jurisdictions, Massachusetts Attorney General Edward W. Brooke appoints John S. Bottomly as head of a "Strangler Bureau" to coordinate the investigation.

As the body count grows, Bottomly, in desperation, calls in a psychic, Peter Hurkos, who pinpoints Eugene T. O'Rourke, a man who seems to fit the profile.

By chance, Bottomly and Detective Phil DiNatale pass by DeSalvo in an elevator, where they had been visiting Dianne, who survived the earlier attack.

Observing the wound on DeSalvo's hand (Dianne, who survived his attack, could remember biting him but not his appearance), the pair make him a suspect for the Boston Strangler murders.

Conventional interrogation is ineffective because the treating physician thinks that DeSalvo suffers from a split personality: he has two identities that are unaware of each other.

The treating physician thinks that DeSalvo could be made to confront the facts but that the shock risks putting him in a catatonic state.

A letter from Commissioner McNamara also made it plain that police personnel would not be authorized to work as extras on the film, a practice that had been approved in two other pictures that went on location in Boston last year.

Fryer couldn't even get permission to take still photos of the offices of the attorney general and the local police commissioner so that they could at least be reproduced back at the studio in Hollywood.

'"[6]The film posits Albert DeSalvo as the Strangler, and depicts him as suffering from a dissociative identity disorder (DID), only confessing to the murders after John S. Bottomly induces his alternate personality.

His actual guilt remains a source of controversy, he was never prosecuted for the Strangler murders, but on separate charges of sexual assault and robbery.

It has no depth, no timing, no facts of any interest and yet, without any hesitation, it uses the name and pretends to report the story of a living man, who was neither convicted nor indicted for the crimes it ascribes to him.

The big things the film tried didn't pan out as that interesting, as the flashy camera work counteracts the conventional storyline chronicling the rise, manhunt, fall, and prosecution of De Salvo.