Lola opened the plonk in court on Wednesday, and it was allowed to breathe for a full 24 hours before Bono's lawyer could contain himself no longer. Paul Sreenan attacked it like a man with a ferocious thirst, determined to get to the bottom of Lola's plonk before the afternoon was out.
Let's call this cheeky little number Chapeau Bono, because its arrival heralded a dramatic development in the hat department yesterday.
U2 say their former stylist, Lola Cashman, took items of band memorabilia following their tour of America in the late 1980s. These included Bono's famous Stetson hat, an unremarkable looking piece of headgear which is apparently more revered in the world than the Turin Shroud.
It was "gifted" to her, says Lola.
Grabbed, more like, say U2. They want to know exactly how she came by it.
In legal correspondence, Ms Cashman was vague on details. At one point, she said she was given a "back-up" hat, as opposed to the actual one worn on stage. (That's right, Bono has a back-up hat in the wings in case of a millinery emergency.)
However, during last year's Circuit Court case, she said the singer gave her the Stetson when he was running around backstage after a concert. Oh, and he was in his underpants at the time.
Paul Sreenan was agog. He thought people would be interested in her tale of Bono in his undies.
Lola, however, chose not to mention this unsettling gobbet of information in the book she wrote about her experiences with the band.
But here's the twist. On Wednesday when she was giving evidence, Lola recalled fondly how, when she asked Bono for his Stetson, "he plonked it" on her head. Not put, or placed, or positioned, but "plonked".
"When was the first time it was ever said that Bono plonked this hat on your head?" he inquired.
Lola paused, twiddled her spectacles in her hands and finally ventured a tentative "Yesterday?" The soft-spoken lawyer paused so this reply could sink in. In the silence, people fell to thinking: if Bono had been a plonker, why didn't she say so earlier?
Back to the sacred Stetson. Lola Cashman thinks it is more than iconic. For her it is "symbolic". Why? "It validated what I achieved on that tour." It can only be a matter of time before Bono's hat is responsible for miracles.
Besides a few old clothes and some souvenir tat, Lola also got a book out of the tour. The court was treated to extracts. Remaining commendably deadpan, Paul Sreenan quoted from the dust-jacket: "Once in a while, a rock biography comes along that redefines the genre." Going on what court number 5 heard yesterday, Lola's isn't it.
Written in breathless schoolgirl prose, the book is a compendium of U2 tittle-tattle and appalling trivia, delivered in an unrelenting tone of awestricken excitement.
But then, Lola had to spice up her story of minding U2's wardrobes if it was to sell. In the face of a charge that she betrayed the band's trust, she murmured that she hadn't written about "who was sleeping with whom". Cue the creak of chequebooks opening across the water. Lola may have to sign up again with publicist Max Clifford, something she did briefly last year.
"I feel I'm just trying to defend myself against allegations that I have an Aladdin's Cave of goods to help myself to," she said yesterday.
If the best examples of the treasure to be found therein are Bono's little breeches and his iconic, symbolic, miraculous hat, then Ms Cashman might just have to write another book.
