“Catherine is my secret garden,” she says quietly when I inquire about the nature of their intimacy. “I have given myself to her, body and soul. She does whatever she wants, whenever she wants, with either or both, according to her pleasure—and her pleasure is also my pleasure.” When I ask what she will do when Catherine dies, she starts to cry.

The back door of Beverly’s cottage opens onto one of two enormous ponds that frame the vast back gardens of the château. In summer, Madame and Beverly occasionally picnic in a little white-and-green rowboat, while in winter the ponds freeze over and the ladies ice-skate on them.

The park is also the setting for other bucolic events—like the warm summer afternoon when, under Madame’s instruction, a local woodcutter fulfilled his lifelong equestrian fantasy. Ever since he was a young man and worked as a groom for a beautiful, rather severe woman, he had aspired to be her horse. Now, naked, barrel-chested, on all fours, his genitals tied with weights, he was outfitted with a leather bridle, bit, and reins, specially made for him by a saddler—“not one of those cheap sex-shop toys,” says Beverly—and ridden, one by one, by each member of Madame’s petit clan, her close circle of dominatrix cohorts of whom she is “chief Queen.” Hierarchy is all, democracy is naught, in this world. Beverly, who briefly trained on the tightrope in South Africa, mounted the beaming man last, standing on his bare back, riding crop at her side in case he slowed down. An afternoon worthy of Fellini.

But it began with Disney. Beverly first saw Sleeping Beauty when she was five or six, but the beautiful princess was of no interest at all to the little girl: “I was fascinated when the queen [the wicked fairy] chained up the prince when he came to find Sleeping Beauty. I saw myself as that woman. I found the idea of chaining a man up so exciting.”

“My fantasy since I was a small child was to dominate a dominating man,” Beverly explains. “That turns me on more than anything, a man who does not want to be dominated—like Sean Connery, a really macho man. The kind of man who has no desire for submission. It’s truly perverse. It’s the power play: who has it, how long you have it for, and what you do with it.” Far from being a “slave,” Beverly, too, is a dominatrix of note, and her relationship with Catherine is increasingly difficult to categorize, even for a connoisseur of the unconventional.

Beverly was a sexually precocious young lady. “Since age 14, I never had boyfriends, but I had lovers,” she says. “For me, a one-night stand meant the fantasy was never destroyed. So exciting! Mini-fantasies I would live out, dominating them.” She smiles: “They hated it! They genuinely hated it. They would get angry . . . but excited. Really excited.” But, she adds, “I didn’t love anyone I was with. Never.”

Beverly first met Catherine more than 20 years ago in Mexico when both were reluctant spouses at an official function. Beverly was married to a French diplomat whom she had met in Soweto and married at age 23. (They remained married until his death, last October, and he and their two children, ages 23 and 27, visited the château regularly.) He was, at the time she met Catherine, the director of the Alliance Française, in Guadalajara, and he was hosting an evening in honor of Alain Robbe-Grillet.

“I saw this tiny woman standing all alone in a corner holding a glass of water while the great man was being fêted, so I introduced myself to her,” Beverly says. She found Robbe-Grillet’s wife to be “literally, immediately” the most fascinating person she had ever met. Their friendship continued when Beverly and her family relocated to Paris. “From the moment I met her, I was obsessed with her. I wanted to hear everything she had to say, I wanted to do things for her, I wanted to take care of her. I wanted to be with her. That little woman has more balls than any man I’ve ever met.”