“I am seven, like seven devils in the bible… or 17, or 70, or 700. But you are only one…”

Fragment Of Fear is in many ways more of a thriller than a bona-fide horror film - at times it veers from odd little psycho drama into an almost "Tinker Tailor Soldier Spy" world of espionage and double dealing.

Tim (David Hemmings) is a writer who's on holiday in Pompeii when we meet him. He's talking to his Aunt Lucy (Flora Robson) about how he "saved himself" from a particularly nasty drug addiction with the aid of a doctor, a psychiatrist and two beefy nurses (so that's hardly "saving yourself" then really, is it?). He then went on to write a book about the subject.

In the next scene Aunt Lucy's dead, found by a group of schoolgirls, the scene lent a kind of spooky inevitability by the tour guide noticing a cloud of flies over the body long before it's spotted.

The group was led by teacher Gayle Hunicutt, and she and Tim strike up a relationship after meeting over the body. "A criminal kills a charitable old lady who spent her life helping criminals - it's ironical, isn't it?" says Tim, adding: "If she had been robbed I could understand it, but there is just no reason!"

We're soon back in England (you can tell because it's raining), and Tim has decided to do a spot of amateur sleuthing to discover why his Aunt died. He noticed at the funeral that she'd been sent a bouquet by the "Stepping Stones" and endeavours to find out who or what this shady organisation is, first going to the old-folks home where many of her friends are staying (which is run by an extremely young-looking Yootha Joyce). The home itself and the people in it seem a little odd, with the one talkative old chap having a weird conversation which ends with Tim saying: "I hope we meet again," and him replying: "You may have to hurry."

On his way back to London on the train, Tim is accosted by a strange woman who forces a letter into his hands. Up until now he's come across as a very polite young man, but when he gets home he tells someone on the other end of the phone: "I met a pathetic dyke on the train…"

It's about this time that the viewer starts to wonder, is Tim everything that he seems, or are we in for yet another tale of a pretty-boy killer bumping off women (Endless Night, The Night Digger)? You'd be forgiven for thinking so, especially when a tape Tim has recently made has some loon cackling away at the end of it and it turns out that the letter the "pathetic dyke" gave him mentions Aunt Lucy's death and was typed on his own typewriter…

The next morning Tim gets a phone call, asking if he got the message. The voice on the other end of the line tells him: "I am seven, like seven devils in the bible… or 17, or 70, or 700. But you are only one…"

Tim hasn't even had chance to leave his flat when a police sergeant arrives, telling him that the woman hit met on the train yesterday is alleging he made "improper and indecent suggestions" to her. Luckily, she didn't make it official, letting Tim off the hook, and Tim takes the opportunity of having a policeman on hand to explain what's been happening to him. The incredulous policeman is told of all the strange goings-on, and Tim finishes by demonstrating the laugh he heard on the tape and then playing it.

"Was that you laughing?" asks the sergeant.

"I don't laugh like that!"

"You just did, sir."

That night, after the policeman has left, Honeycutt arrives to find a very sweaty Tim convinced that he's being watched and not letting her put the lights on.

The film now begins to get very strange. Tim is being followed (by Arthur Lowe, of all people), but is he just an hallucinating ex-junkie, or was there more to Aunt Lucy's life than was apparent? And who are the Stepping Stones? And why do people keep dying?

Fragment Of Fear is a film which keeps you guessing, and therefore entertained, all the way through (the scene where Hemmings and Honeycutt get married is choc-full of early 70s paranoia - "Put your glasses on!"). There's also more than a hint of Repulsion in every scene set in Tim's sweaty apartment.

Everyone seems to have a hidden agenda, and although slightly more coherent, it also smacks somewhat of Hemming's other bonce-scratcher, Blow Up (particularly when he comes across a crowd watching an old druggie mate of his shooting up in an alley, and later gets mugged and wakes up with a needle in his hand).

If you fancy a bit of blackmail, a touch of conspiracy and a soupcon of insanity, you could do worse than tracking down Fragment Of Fear.