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LONDON - Amid the neoclassical splendour of the ballroom in the Belgravia mansion that once belonged to the Guinness dynasty, the Irish ambassador's annual press party was going well.
By late in the evening on December 5, about 300 guests had been announced at the London embassy.
According to veterans of the embassy's legendary hospitality, the wine - not to mention the Guinness, gin and whiskey - flowed freely.
As one guest put it: "It was as if the waiters had been given a quota of wine that they had to get rid of."
The Right Reverend Tom Butler, Bishop of Southwark, says he has little recollection of the night.
What followed is a tale of clerical amnesia and toe-curling allegations which have elevated the 66-year-old Anglican bishop from cerebral prelate to Christmas party legend.
Butler said he drank "a glass or two" of Portuguese red. He was not, he insists, drunk.
What is certain is that by the time he reached home, Butler was dealing with a nasty head wound, a missing mobile phone and calls for his resignation over a number of unanswered questions, not least an apparent late-night encounter with the back seat of a stranger's Mercedes and an unspecified number of cuddly toys belonging to the owner's 11-month-old son.
The next day he told the congregation in nearby Dulwich that he had apparently been mugged and was unable to wear his mitre because of the swelling caused by his injuries. Otherwise, details of what happened between leaving and arriving at his home were, he said, a blank.
Others, however, have stepped forward to fill in the gaps.
Paul Sumpter, a businessman from Beckenham in Kent, described how at 9.30pm on the night of the party he was at a bar and heard the alarm on his Mercedes parked on the aptly named Crucifix Lane, close to Butler's base at Southwark Cathedral.
"I rushed outside and found the doors of my car open and the man who seemed drunk with his legs hanging out of the back, chucking my son's toys about," he said. "He staggered about, fell over and hit his head against the side of pub. He then fell on the pavement and knocked himself out cold."
Three days later Sumpter's wife found the bishop's briefcase in the car.
Yesterday, the bishop broke his silence on the matter to say he is suffering from amnesia and undergoing medical tests, amid suggestions he may have suffered a minor stroke.
On the BBC's Today programme, he said he had not recovered any memory since the early stages of the party.
"It is very worrying. I still have amnesia," he said. "I am having extensive medical tests."
Under questioning, Butler strenuously denied that he was the worse for wear.
"I have been going to receptions for 20 years as a bishop. It was entirely out of character if I was drunk. There are strange elements to this story.
"I am very careful at such receptions.
"Normally I have a glass or two of wine and I enjoy talking to people. I don't get drunk frequently. I wouldn't be able to do my job if I did."
- INDEPENDENT