It all started with a scream in the dead of night which caused Bryan Hale and his wife to sit bolt upright in fear.
Looking out of the window, they saw a mysterious black creature bound up the garden steps.
Next morning, they found a large paw print in their garden.
Assuming it had been a dog, Bryan did not give the incident much thought, until sightings of what was thought to be a puma not far from the couple's home in Hurstpierpoint two weeks later.
Bryan started researching the possibility that big cats like the Beast of Bodmin were roaming the Sussex countryside.
That was in 1982.
Bryan is now an amateur cryptozoologist, someone with an interest in out-of-place animals.
He has more than 300 letters from Sussex residents convinced they have seen pumas, lynx or black leopards.
In the last week he has received another six letters.
Along with more than 150 questionnaires, these sightings are the basis for a book Bryan has started writing about the big cats of Sussex.
He said: "In the past, people wouldn't admit to seeing big cats because they were embarrassed - they didn't want to be lumped together with Loch Ness monster loons.
"Now it's respectable. I've had letters from doctors, lawyers, farmers - people who would gain nothing from making it up."
In the last few years, Sussex has shot up the league of big cat sightings published annually by the Fortean Times Journal of Strange Phenomena.
Bryan, who now lives in Lodge Lane, Keymer, and who works as a nurse in a care home, said: "Some people may still think we're mad but Asian swamp cats, lynx and even a black leopard have been killed by police or hit by cars so we know they do exist.
"A couple of weeks ago I saw a big cat between Ansty and Burgess Hill as it streaked across a field. I knew it was a puma, though I can't prove it. It's the closest I've come to one.
"A couple of days before someone saw one near Goddards Green and a few days later a taxi driver saw one in Ockley Lane, Keymer.
"People have admitted letting pumas, lynx or black leopards loose in the country before it became illegal in the early Eighties.
"The Sussex countryside is a perfect habitat - it's like a giant larder with deer, sheep, lambs and rabbits.
"I hope these beautiful cats will be recognised as a new indigenous British fauna and given some form of protected status."
To contact Bryan, call 01273 844468 or email bryanandeileen@btopenworld.com
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