When adulterous wife Lisa Baumer (Evelyn Stewart) loses her husband in an exploding plane, she inherits a million dollars. Although the insurance company suspect she conspired with her lover to murder Mr. Baumer, she maintains her innocence. Shortly afterwards, Lisa is stalked by another ex-lover who blackmails her over past statements about wanting the old man dead. She agrees to pay, but later arrives at his apartment to find he has been stabbed to death. Flying from London to Athens to collect her fortune, Lisa is trailed by Peter Lynch (George Hilton), a suave private investigator working for the insurance company. He saves her life when she is threatened by yet another set of blackmailers, this time her husband’s former mistress (Janine Reynaud) and her knife-wielding accomplice. Peter persuades Lisa to go to the police, but later she is knifed to death by a killer in black leather. A sardonic local police inspector (Luigi Pistilli) and Interpol agent John Stanley (Alberto De Mendoza) take charge of the investigation, while Peter finds an ally in sexy crime photographer Cleo Dupont (Anita Strindberg). They set out to crack the case themselves.
Taking its title from a pair of scorpion shaped cuff-links that prove a vital clue, The Case of the Scorpion’s Tail springs from another deliciously twisted and twist-laden screenplay penned by giallo veteran Ernesto Gastaldi, working in tandem with co-writers Sauro Scavolini and Eduardo Maria Brochero. A super stylish Bruno Nicolai score is in perfect synch with the arresting imagery woven by underrated Italian jack-of-all-genres Sergio Martino, although the terrible model aeroplane used in the explosive opening sequence marks a rare misstep.
As in the Gastaldi-scripted Death Walks on High Heels (1971), the plot abruptly bumps off one heroine then switches focus from one protagonist to another. Evelyn Stewart is rather frosty as the persecuted Lisa, which is a flaw given we are meant to empathise as she his faced with blackmailers around ever corner, only to come to a nasty end. Fortunately, Anita Strindberg - looking considerably more glamorous than in her later Martino collaboration, Your Vice is a Locked Room and Only I Have the Key (1972) - proves more engaging. Indeed, Cleo is scripted as one of the brighter, more intuitive heroines in the giallo genre. Nevertheless, typical early Seventies sexism rears its head, as the price of being emancipated leaves Cleo a terrible cook. “Darling you are much better in the bedroom”, remarks Peter in suitably smarmy fashion.
While ambitious, the multi-perspective narrative prevents viewers from growing emotionally involved in the mystery. However, Martino masterfully teases as to the identity of the killer who - in his slouch hat, black mask and leather suit - ranks among the most stylishly dressed giallo murderers. The murder sequences are expertly orchestrated with great cinematic flair. In particular the stalking of Jess Franco and sexploitation regular Janine Reynaud - e.g. Kiss Me Monster (1967), I Am A Nymphomaniac (1971) - which features the spine-tingling use of a straight razor to undo a door latch, several years before a similar scene in Suspiria (1977).
Martino throws in some grindhouse crowd-pleasing gore, including an explicit eye-gouging, and nudity alongside an extended sequence where the lovely Strindberg explores an underwater cave in a skimpy bikini, her striking blue eyes ably conveying the sheer terror of her discovery. But this is mostly all about those snakelike plot twists which ensure that while this might not be as top-drawer as Martino’s Edwige Fenech vehicles The Strange Vice of Mrs. Wardh (1970) and especially All the Colours of the Dark (1972), it still ranks among the most entertaining gialli of the era.