It made for an unlikely national obsession: an 18-carat gold, jewel-encrusted hare buried somewhere in Britain, and the fiendishly complicated clues to its secret location contained in a lavishly illustrated children's story.

Kit Williams sparked the nation's biggest treasure hunt 30 years ago with his book Masquerade, which sold 2m copies worldwide. But the public response was so overwhelming – Williams received more than 100 letters a day for two years – that the publicity-shy author and illustrator became a virtual recluse.

Today Williams was back in the public eye, reunited with his handmade amulet for the first time in three decades. The makers of a BBC documentary traced the owner of the golden hare to Egypt after an appeal on Radio 4.

"It is wonderful to see it after all these years," said Williams. "It was a very emotional moment. I had not remembered it being as detailed. The bells jingled and it sparkled in a way I had forgotten."

The hare's trail has been a complicated one since it was buried by Williams in Ampthill Park, Bedfordshire, one night in 1979 in a secret ceremony watched by a celebrity witness, Bamber Gascoigne.

Williams's book used 15 detailed paintings to tell the story of Jack Hare, who is charged with carrying a treasure from the moon to the sun. On arriving at the sun he discovers he has lost the treasure, and it is left to the reader to find it.

The riddle was finally solved by two Manchester teachers in 1982, but by then the amulet had been claimed by a searcher who, it emerged, was given the approximate location through a connection with Williams's former girlfriend.

The hare was later bought by a mystery buyer for £31,900 at a Sotheby's auction in 1988. Williams had tried to buy it but was outbid, and it has remained unseen in private hands for more than 20 years.

Williams withdrew his artwork from public display after he grew uncomfortable with the huge public attention generated by the hunt, which at the height of his fame saw him appear on Terry Wogan's BBC1 chatshow.

"I could not take the razzmatazz," he said. "There was pressure on me to do all sorts of things and I just did not want to do that. I felt I lost touch with myself for a little while. I worked on paintings but I never put them on public show."

Williams, 63, was reunited with the hare – and Gascoigne – by the makers of a BBC4 documentary, The Man Behind the Masquerade, to be shown this autumn.