And so all that remained for Charlotte Middleton—she’d returned to her maiden name when she learned the extent of her husband’s participation in a plot to kill thousands in Washington, D.C.—was the work she was doing for the Volunteers. Her father had told her he needed her. It was possible that he did. Protesting, she’d said, “Harry, I can’t. Given how pointless, how empty . . . Damn it, I wish I could explain so you’d know.” “Charley,” he replied, “when I think about what my life would be without you, I know.”

At a kiosk near the Théatre Marigny, she bought a sandwich of thin slices of ham, a sliver of gruyere and salty butter on crunchy bread, and a bottle of Badoit, and sat on a bench in a stream of sunlight, the Étoile and the Arc de Triomphe in the distance, the relentless traffic coursing along the cobblestone. In an attempt to dispatch her thoughts, she recalled some of the research she’d done for the Volunteers. Her mind wandered to Connie Carson and the bravado instilled in every task undertaken by that little Texas firebrand, and then to Wiki Cheung’s fascination with Second Life and how the adorable 19-year-old computer geek had given himself a black avatar with a ’70s Afro and chiseled body any athlete would kill for. “Try it,” Wiki had suggested. “Everybody needs someplace to be somebody new.” As soon as the words passed his lips he recoiled in embarrassment. “I’m not saying your life is not good, Charley. No, what I’m saying—I’m saying, Charley, the game—Maybe you’ll make new friends—If you want new friends, Charley . . . Ah damn it . . . ”

Around the same time, Leonora Tesla, who she admired more so now that she understood what the Volunteers had achieved, had asked her to join her for a drink after hours. They’d gone to a Latin lounge in Dupont Circle, where they were surrounded by careless singles floating between youth and responsibilities, six fresh faces crammed at tables for four. Giddy conversations rose over bubbling music. “Charley,” Tesla shouted, “here’s my advice: Don’t take any advice. Listen to your own heart in your own time.”

Now on the Champs Élysées, reflecting on those memories four-thousand miles away, Charley watched a tour bus scored with Hangul script wheezed to a halt, blocking traffic. She grimaced as taxi horns blared, and then returned to her solitude.

Perhaps 30 yards behind Charlotte Middleton in the park was a self-satisfied man in his 50s, tanned with salt-and-pepper hair. His blue suit, cut to perfection, was impressive even in the arrondissement that hosted the houses of Saint Laurent, Dior, Chanel and Lacroix. As he sat, he removed a silk handkerchief from an inner pocket and wiped the sides of his Berlutti shoes, removing a coat of dust. His cell phone vibrated as he returned the kerchief to its post.