For a place that’s now a family-run bed and breakfast with a sleepy labrador padding round the grounds, Boleskine House on the eastern shore of Loch Ness is strangely ubiquitous in the local lore of oddity.

This low-slung, pink-walled house is where the Satanist-cum-fraudster Aleister Crowley claimed to have raised the devil in 1912. The house was then owned by Crowley aficionado Jimmy Page, the guitarist of Led Zeppelin. Before that, though, Boleskine accommodated, or at least its grounds did, a further celebrated charlatan, even if Frank Searle was concerned less with demons than with toy submarines and old socks.

Searle, whose death was announced last week after a documentary film-maker went searching for him in Fleetwood, Lancashire, and discovered he had died in March, was no stranger to peripatetic living in the vicinity of Loch Ness. He camped in a tent beside the loch for more than three years. After a similar stint at Boleskine, he moved into a mobile home at Lower Foyers. A decade later he vanished, driven away by the collapse of his Loch Ness monster fantasies.

Whatever his movements, Searle’s belief in the Loch Ness monster never wavered, mainly because he had assembled much of the myth in the first place. Searle’s ingenuity and the believability of his pictures made him a tabloid cause célèbre in the first half of the 1970s. Among the scientific community, however, his career of photographic hoaxing is still a subject of debate. The monster-hunter Paul Harrison thought Searle’s snaps at least kept the search for Nessie in the public’s mind. Henry Bauer thought it impossible to calculate “how much harm” Searle’s hoaxes had done the cryptozoological cause. But how Searle truly regarded his own “work” is among the secrets he took to the grave, along with whether he was ever sincere in his pursuit of Nessie.

Inspired by Constance Whyte’s evangelical 1957 book More Than a Legend, Searle’s dedication was evident from his 14-year vigil by Loch Ness (he claimed to have scanned the loch for more than 20,000 hours). At the same time he relished the media attention he garnered from being a monster-hunter. Chasing Nessie was briefly a public craze and Searle was its ringmaster, sporting a badge reading “I’m Nearly Famous” and hoping to fill his tent with a harem of assistant monster huntresses. One he did snare was Lieve Peten, a Belgian assistant in the late 1970s, whose website still features an appeal for knowledge of Searle’s whereabouts.

Searle hadn’t been seen at Loch Ness since 1983. He left directly after Adrian Shine, a long-time scientific investigator at the loch, complained that an unpublished book Searle had written defamed him and plagiarised material from other Nessie books. Searle’s book was dropped by its publisher. “Searle threatened at the time that, because of this book incident, he’d be a thorn in my flesh for many years to come,” says Shine, “but I never saw or heard from him again.”

Shine remembers Searle as “a hard-bitten, slightly suspicious, shifty character, a chap with chips on both shoulders”. He first encountered him in the early 1980s at the exhibition of Searle’s Nessie photographs that Searle ran from his caravan. “It was a rather egocentric exhibition,” he recalls, “full of newspaper clippings about Searle himself. Ego is always a real giveaway with those who pursue the Loch Ness monster.”

Searle arrived at the loch in 1969, having served as a sniper in the army (he lost the lower half of his left leg in Palestine) and worked as a greengrocer in London. Shine doesn’t believe Searle was wilfully duplicitous from the outset. Rather, he says, Searle came to the loch with the intention of capturing the creature on film honestly. “I think he wanted to be the man in his field,” says Shine.

“The detail in his photographs suggests he very carefully faked them, so he knew what he was up to. But, initially, he probably had very high hopes of seeing and photographing the monster, a hope that went unrequited, sadly for him. He didn’t get what he wanted quickly enough, so he hurried the process along a bit.”

This disappointment was compounded in the mid-1970s when Loch Ness became a focus for well-resourced researchers, often from overseas. He was particularly jealous of celebrity status, says Shine, status of the type Robert Rhines gained with his half-persuasive sonar shots of Nessie in 1975.

“He soon felt, I think, there wasn’t enough to photograph, not enough money, not enough women,” says Shine. “At heart he was a main chance merchant, someone who thought the definitive photograph was merely a matter of hanging around a bit. The monster has a habit of proving such people wrong.”

By the 1980s, the scientific community had acknowledged Searle as a fraud and his celebrity had faded so much that only a shot of Nessie with a spaceship could guarantee him coverage in the papers. “I think Searle assumed all the other researchers were as duplicitous as he was,” says Shine. “Their popularity made him all the more bitter.”

He disappeared amid rumours that he’d gone treasure hunting. So far, nothing is known about Searle’s movements between 1983 and March 26, when he died aged 84.

Shine won’t be mourning his old nemesis, no matter how superficially persuasive his fakes or how colourful the life that produced them: “Searle was everything the public believe serious Nessie researchers to be: fraudulent, cynical, a bit mad. He was an unlikeable rogue, really.”

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