Dark Intruder (1965) ***

Sumerian demons, Siamese twins separated at birth, a serial killer, oceans of fog, the flower of the mandrake, a climax that revolves around “it’s in his kiss” and a picture so shorn of light it could easily have been titled Dark Fiancé or Dark Wedding. Thematically truncated, too, and you get the feeling that with a little bit more narrative expertise and budget this could have been spun out into something that fitted in with the decade’s later spurt of horror a la Rosemary’s Baby (1968). There’s the bonus of Leslie Nielsen (Airplane, 1980) in a straight part though one which allows him a fair quota of quips.

In San Francisco 1890, occult expert and straight-down-the-line man-about-town toff Brett Kingsford (Leslie Nielsen) is surreptitiously engaged by the cops to investigate a series of brutal murders. Beside each corpse, the killer has left a memento, a tiny statuette that is traced back to Sumerian times, a demon – similar to the larger kind that turn up at the archaeological dig at the start of The Exorcist (1973) – banished from Earth and which attempts to return by entering another person’s body though presumably none of the four victims coming up to scratch.

Among the dead is Hannah, who had been involved in an archaeological expedition and later adopted a mysterious child. She has a connection to Brett’s friend, antiques dealer Robert Vandenburg (Mark Richman) who is engaged to be married to Evelyn Lang (Judi Meredith), another friend of Brett. Though Brett consults Chinese expert Chi Zang (Peter Brocco) and is attacked by the titular intruder who leaves him with claw marks on his shoulder, the bulk of the detection falls to Robert, who exhibits odd behaviour, standing in a daze, sleepwalking, going off in the wrong direction, suffering from blurred vision, and with a strange scar on his spine. He encounters the mysterious Professor Moloki (Werner Klemperer), face concealed, who tells him all will be revealed on the eve of his wedding.

The killings don’t stop, Brett no closer to catching the killer, and no further evidence forthcoming and the tale falls on the shoulders of Robert who is convinced from his own odd behavior that he is the killer. Eventually, he starts to work out the strange elements of his own life and the “invisible force” he is constantly fighting.

Turns out he was the Siamese twin separated at birth, and that Hannah had brought up the other, deformed, twin, who now wants his twin’s life – and wife. All we see of the creature is the claw, the rest of him hidden under a cloak or shuffling along behind curtains. The pair grapple in the darkness and it appears the bad twin is slain.

But is he? It’s Evelyn who gives him away, revolted by his kiss, and the matter is resolved. So really no more than the assembly of an interesting horror story. The claw is well done but as I said most of the detection comes from the mind of Robert rather than the occult detective working up the clues. But the dapper Brett is good value, keeping chatterbox Evelyn in check, and putting on his best Basil Rathbone impersonation.

As a bonus it’s insanely short, barely an hour long, which would have put it squarely in the B-feature category – but of two decades before, not of the mid-1960s. Turns out this was a pilot for a television horror series that wasn’t picked up by any of the three U.S. networks so was extended enough to be feature-length. The actors try desperately to add characterisation to their thin parts, Leslie Nielsen (Beau Geste, 1966) and Judi Meredith (Queen of Blood, 1966) best at that.

Harvey Hart (Bus Riley’s Back in Town, 1965) directed from a script by Barre Lyndon. The movie was released by Universal, who had Nielsen on an exclusive seven-year contract.

The sum of its parts without much else, but intriguing tale calling out to be extended – or remade.