THE SNORKEL. Hammer Films, 1958. Peter Van Eyck, Betta St.John, Mandy Miller, Gregoire Aslan, William Franklyn. Directed by Guy Green.

   Several years ago, Candace ‘Candy’ Brown (Mandy Miller) saw her father drown and has always believed that Paul Decker (Peter van Eyck) was responsible. Now Candy is a teenager, Decker is her stepfather, and her mother has apparently gassed herself to death in their Italian villa.

   Candy is convinced that Decker killed her too. For one thing, there was no suicide note. Both the local police inspector (Grégoire Aslan) and British Consulate Mr Wilson (William Franklyn) believe the death was self-inflicted as the door was locked and the windows were sealed. Even her friend and nanny Jean Edwards (Betta St. John) thinks Candy is delusional.

   Unbeknownst to them, Decker is indeed the murderer and let in the gas himself before escaping through a trap door and hiding beneath the floorboards, where he donned a snorkel to prevent his own death from asphyxiation.

   Candy openly accuses him of murder, but Decker presents his passport as proof that he was across the border in France and was therefore not in the country at the time of her mother’s death.

   Undeterred, Candy investigates and soon figures out that a snorkel was somehow involved. Decker, meanwhile, becomes romantically interested in Jean and slyly suggests they have Candy committed to an American asylum while they start a new life together. However, as she moves closer to the truth, Decker decides more drastic action is necessary. He has the means, after all…

   The Snorkel is a thriller from Hammer, one of several they made which now cower in the tall, distinctive shadows of Frankenstein and Dracula. These play like Hitchcock on a lower budget and several came from the pen of Jimmy Sangster, who wrote many of their most iconic films and as such remains at least partly responsible for the company’s iconic cult status across the decades.

   The story for this one was dreamed up by actor Anthony Dawson (remembered for his superb performances in Dial M for Murder, Midnight Lace, Dr No, and an episode of The Saint), and though the murder method may lack the ingenuity of other locked room mysteries, it looks less unlikely when offered up first. An explanation at the end of the film may have seemed like a slight cheat.

   While Sangster’s later Taste of Fear would imperil a paraplegic, he focuses The Snorkel on another vulnerable female in teenager Candy, played by the slightly too old child actor Mandy Miller. This gives the film a faint Nancy Drew feel, though Candy has few deductions and no clues, while most of the developments are due to coincidence and an unshakeable conviction that Decker is the murderer.

   The detective work is limited to a furtive search of a hotel room before being dropped altogether and replaced with brassy confrontations and sullen assertions, while an inspection of the villa at night is simply there to generate some spooky atmosphere and slyly set up the finale.

   German actor Peter van Eyck (best known to English-language audiences for his appearance in Richard Burton-starring The Spy Who Came in from the Cold) acquits himself well as Decker, suave and serenely disappointed at one moment and blank-eyed and sinister in the next. He looks like a cross between Derren Nesbit and Jack Cassidy, which is fitting as this is basically an episode of Columbo (in the first few minutes, as he commits the murder, you expect to see the thick, yellow credits of that ’70s classic).

   The Snorkel doesn’t, however, offer a slyly formidable opponent, and wastes William Franklyn, potentially a perfect fit, in a negligible role. Really, though, it’s not that type of thriller in the first place, and Decker isn’t caught through any mistake of his own. This is an atmospheric, psychological thriller of the ‘damsel in distress’ variety, not a detective story.

   Though low-key, it features some excellent location work on the Italian Riviera, a tense climax that also teases something ruthlessly cold-hearted, all sewn up in a brisk, undemanding 74 minutes.

Rating: ***