They were supposed to be confidential chats between France's richest woman and her financial advisers, with topics ranging from secret Swiss bank accounts to her gift of a private luxury island to a friend.
But someone slipped a recorder into the room, taping everything. The butler says he did it.
His secret recordings, recently leaked to the media, have embarrassed the French political establishment at the highest levels and prompted tax authorities to announce a thorough audit of L'Oreal heiress Liliane Bettencourt's fortune.
The 21 hours of tapes may also force the delay of this week's high-profile court case pitting the billionaire Bettencourt against her only child. As the trial opens on Thursday, a court in the Paris suburb of Nanterre will decide whether to push the case back for more study of the tapes.
The case started when Bettencourt's daughter, Francoise Bettencourt-Meyers, alleged that a charming society man had conned her 87-year-old, mentally frail mother out of cash and artworks worth euro1 billion ($1.2 billion).
Celebrity photographer Francois-Marie Banier a 63-year-old dandy who has befriended stars from artist Salvador Dali to actor Johnny Depp is to stand trial for exploitation. Banier insists he did not take advantage of his older friend.
The younger Bettencourt says she just wants to protect her elderly mother. And the elder argues that she has her wits about her and can do whatever she wants with her money.
It's a dilemma familiar to many families but Bettencourt is No. 17 on Forbes magazine's list of the richest people worldwide, with a net worth of $20 billion.
Interest in the case shot to a whole new level once French media released printed and audio excerpts of the secret tapings by Bettencourt's former butler, Pascal Bonnefoy.
Bonnefoy made the tapes at his own initiative to protect himself, initially fearing Banier's influence over his boss might cost him his job, said the butler's lawyer, Antoine Gillot. Though a security company had scoured the house looking for microphones, Bonnefoy simply carried a cheap recorder into the room when he brought refreshments on a tray for Bettencourt's business meetings, the lawyer said.
"I hope these recordings will help clarify things and prove that this woman is in danger, that she is surrounded by people with no scruples," Gillot said.
Bettencourt's lawyer, Georges Kiejman, is seeking a delay to the trial so experts can verify the tapes are the real thing. Gillot vouches for the authenticity of the recordings and the excerpts in the media, which give clues to Bettencourt's mental acuity. In them, advisers speak to her as though to a child, and she is sometimes confused.
At one point, adviser Patrice de Maistre reminds Bettencourt that she signed over her private island in the Seychelles to her younger friend, Banier.
"I wanted to give him an island?" she asks, puzzled. The tapes have had serious political implications: Maistre was caught telling Bettencourt he hired Labor Minister Eric Woerth's wife because the minister asked him to. Florence Woerth has since resigned, and the couple have denied there was a conflict of interest.
Until March, Woerth was budget minister, in charge of pursuing tax dodgers. Woerth has been strongly backed by President Nicolas Sarkozy, and the government all week has been sharply fending off attacks from the leftist opposition over the affair. In the tapes, Bettencourt and Maistre also are heard discussing undeclared Swiss bank accounts. Maistre told Le Figaro newspaper this weekend that the heiress had euro78 million ($97 million) in two foreign accounts, and he promised to get her affairs in order. Bettencourt's daughter, a writer, says she didn't pursue the case for money. She is in line to inherit all of her mother's shares in L'Oreal, one day giving her ownership of more than one quarter of the cosmetics giant.
Bettencourt-Meyers says that if the court orders Banier to return the gifts, she wants the money to go to charity.
She and her mother no longer speak, but in an interview published this weekend in Le Figaro, she said, "I want her to know that I never stopped loving her."