Pickles, the mongrel dog who found the World Cup in a London street after it had been stolen three months before the 1966 finals, became a bigger story than that year's general election. Forty years on, Jamie Jackson traces the dramatic events - and hears there may be more to come

On a Sunday evening in March 40 years ago, David Corbett left his ground-floor flat in Norwood, south London, to make a telephone call from the kiosk across the road. With the Thames lighterman was Pickles, the four-year-old mongrel he had taken off his brother John's hands, when he was a puppy, because he chewed furniture.

'I put the lead on Pickles and he went over to the neighbour's car,' recalls Corbett, now 66. 'Pickles drew my attention to a package, tightly bound in newspaper, lying by the front wheel. I picked it up and tore some paper and saw a woman holding a dish over her head, and disks with the words Germany, Uruguay, Brazil. I rushed inside to my wife. She was one of those anti-sport wives. But I said, "I've found the World Cup! I've found the World Cup!"'

Corbett, or more precisely, Pickles, had indeed discovered the missing Jules Rimet trophy. Yet, if the Metropolitan Police had not bungled an operation two days earlier, when a ransom demand went wrong, Pickles would not have found the trophy and his place as lead character in a tale that, even today, may not be fully over.

The trophy was stolen on 20 March 1966, a week before Pickles' intervention, from the Methodist Central Hall in Westminster where it was being exhibited in a glass cabinet. Five guards were detailed to keep constant watch. On the Sunday, though, the guard stationed next to the trophy had the day off. With the others enjoying a cup of coffee or a call of nature, it was only when George Franklin finally inspected the case just after midday that he discovered the theft. The thieves had broken in through the back doors.

For the Football Association and Sir Stanley Rous, the English president of Fifa, this was the nightmare scenario. Three months before hosting the 1966 World Cup, there was no trophy.

The investigation began. Detective Inspector Bill Little heard witness statements from senior guard Frank Hudson and Margaret Coombes, a woman attending a Sunday-school service in a different part of the hall. Both saw a man loitering by the gents. Although their descriptions differed, the police announced they were searching for just one thief.

Meanwhile, the FA attempted to deal with the crisis. Before the theft became public, the FA secretary, Denis Follows, visited silversmith George Bird at his workshop in Fenchurch Street. Follows asked Bird to make a replica of the trophy from the same solid gold as the original, and was told nothing else other than to keep his mouth shut. Very few people, including Rous, knew about the visit.

Once the world discovered the theft, a deluge of crank theories arrived at Scotland Yard. One man wrote to say that his clock had told him the trophy was in Wicklow, Ireland. A Susanna Bell in Chile believed 'a coloured man' was the thief. Adolf Hieke sent a photograph from a German newspaper and placed an 'X' on it against the man he believed to be guilty.

With the Metropolitan Police an international joke, Little handed over the investigation to the Flying Squad's top man, DI Len Buggy. His break came when the Chelsea and FA chairman Joe Mears was phoned by a man calling himself Jackson. 'There will be a parcel at Chelsea football club tomorrow. Follow the instructions inside,' he told Mears. On the Wednesday after the theft, it arrived containing part of the Jules Rimet. A ransom note demanded £15,000 in five and one pound notes.

'Dear Joe Kno (sic) no doubt you view with very much concern the loss of the world cup...' it began. 'To me it is only so much scrap gold. If I don't hear from you by Thursday or Friday at the latest I assume its one for the POT.' Jackson called, seeking confirmation that Mears had the parcel. 'Give me £15,000 on Friday and the cup will arrive by cab on Saturday,' he said.

As Jackson had requested, Mears posted the message, 'Willing to do business Joe', in Thursday's edition of London's Evening News. But he ignored the warning not to tell the police. On Friday, Buggy arrived at Mears' home but the FA chairman, an angina sufferer, had to go to bed because of stress. So Buggy arranged with Mrs Mears that he would pose as her husband's assistant 'McPhee' when Jackson called.

After some hesitation, Jackson agreed to a rendezvous in Battersea Park. Buggy arrived in Mears' fawn Ford Zodiac with £500 in bundles and the remainder of the ransom made from newspaper. He was told to drive around south London for 10 minutes, before he and Jackson turned off Kennington Park Road. Now, though, the operation went wrong and history opened its door to Pickles. Jackson saw a Transit van and guessed correctly that it was Buggy's back-up team. He tried to escape, but was arrested.

The thief's real name was Edward Betchley, a 46-year-old former soldier who had served in the Royal Armoured Corps during the Second World War in Egypt and Italy, before being demobbed with an 'exemplary character' in January 1946.

With a previous conviction in 1954 for receiving tins of corned beef, Betchley was hardly bigtime. And at Rochester Row police station, he insisted that he was just the middleman, paid £500 for his part. All Betchley added was that the man behind the theft was known as The Pole. It is not clear if he actually existed.

All that mattered now, though, was finding the trophy. According to the Channel 4 programme, Who Stole the Cup?, which will be shown next month, Chief Superintendent John Bailey was offered a deal by Betchley. He wanted a lady friend to visit him at Brixton prison. If she was followed, Betchley said, then the cup's location would not be revealed. Bailey agreed. Two days later Pickles found the trophy.

The media attention was worldwide and, Corbett says, Pickles enjoyed it. Before it began, though, Corbett had to deal with the theory that exercised the police from the moment, breathless and still in his slippers, he arrived at Gypsy Hill police station in Crystal Palace and was taken to Scotland Yard. 'I was suspect number one,' he says. 'I went into this bloody great incident room with twenty coppers taking calls. I heard one say, "We've just searched the Northern [Tube] line because someone said it was under seat number seven."

'They questioned me until 2.30 in the morning. I wondered if I should've chucked it back in the road. I was up at six the next day for work.'

Corbett recalls: 'The general election was due but this knocked Harold Wilson off the front pages. When my mates realised they said, "Bloody hell. I bet you nicked it!"' Eventually, though, Corbett was cleared.

Now Pickles began the life of a celebrity. He starred in a feature film, The Spy with the Cold Nose, and appeared on Magpie, Blue Peter and many other TV shows. He was made Dog of the Year, awarded a year's free supply of food from Spillers and there were offers to visit Chile, Czechoslovakia and Germany.

'But I would've had to put Pickles into quarantine for six months and he was only a pet, so I didn't think I could do that,' says Corbett. How did he find the constant attention? 'I got myself an agent. The same as Spike Milligan's. He made me £60 a day, bloody brilliant! He would call and my [ex] wife and I would meet him and his girlfriend and go drinking Champagne.'

Corbett's agent arranged entrance to the party on the evening of England's 4-2 victory over West Germany in the World Cup final. 'The streets were full of people. The players were out on a large balcony [of their hotel in Kensington]. I went in with Pickles under my arm and Bobby Charlton, all of them, picked him up. But I ate with the wives in a separate room. The women weren't allowed upstairs. They made a fuss of the dog, but God they were upset. "Our husbands win the World Cup and the FA banish us down here!" they said.'

What Corbett was unaware of, though, was the secret plan that had been successfully carried out earlier that day by the FA to ensure they would not be embarrassed again. Once the trophy had been presented by the Queen to Bobby Moore, plain-clothes officer Bob Geggie was detailed to shadow the England players around the Wembley turf on their lap of honour, watching the trophy closely. Geggie can be seen next to the team on film and photographs taken of those moments.

And, unknown even to Geggie, a Wembley policeman, PC Peter Weston had positioned himself near the changing rooms with Bird's replica, which had still been made, although from base metal, for the next stage of the FA's scheme. With the team celebrating inside, Weston took his chance. He tells the C4 programme: 'Luckily the [real] trophy was near the entrance where Nobby [Stiles] was sitting. I said to him, "I'll have that, you have this." He looked bemused as I legged it, but never said a word. But that meant from when I took it off Nobby, the trophy was a replica. Over the next four years I saw it paraded, in newspapers, on TV, and always chuckled to myself.'

But the tale of the Cup was hardly over yet. In 1970, Bird's replica was returned to him and the original given permanently to Brazil. In 1983, the original was stolen and never returned. The replica, though, went up for auction 14 years later at Sotheby's. It was bought for £254,000 by Fifa, eclipsing the reserve price of £30,000, and is now at the National Football museum in Preston.

Mears died on 1 July 1966 from the angina attack brought on by the theft, while Betchley, having served the two-year sentence he received for demanding money with menaces, died in 1969 of emphysema.

And Pickles' luck also ran out the year after his great find. 'My six-year-old had him on a choke lead,' recalls Corbett. 'He shot after a cat and pulled my son over, before disappearing. I looked for over an hour. Then, in the gardens behind my house I saw him up on a tree. His chain was around the branch. Pickles just hung there.'

Corbett buried him in the back garden of the house in Lingfield, Surrey, that the reward money had bought. 'I received £3,000 and paid £3,100 for this house,' says Corbett, who still lives there.

Observer Sport has contacted Betchley's daughter, Marie, but she refuses to speak. 'I knew nothing about football then,' she says. 'And I'm not interested now. I can't understand what people would be interested in 40 years down the line.'

The fascination is much to do with a dog named Pickles, and a story that refuses to die. Even now, there must be a question over whether Betchley really was the only one involved. 'I've been offered a few hundred pounds from some newspapers,' Marie's husband, John Stringer, says. 'It'll take a lot more for me to open my mouth. But I handled all my father-in-laws legal affairs at the time. And let me tell you, there is a twist that has yet to be revealed.'

It is a shame that Pickles is not around to sniff it out.