He cocked his head and I followed him. “We’ll start with the Napoleon angle, I figure,” he murmured. “The clue said ‘above the coronation site,’ which is at the altar. So we’ll check around and above there.”

We got as close as we could to the altar, but the area directly around it was roped off. Its main focus was a giant golden cross looming over a marble pietà, and there were innumerable nooks and crannies around it where a clue could be hidden. Jack circled behind it while I stood near a British tour group and inspected it as best I could from the front, then the sides. I pointed down one aisle and headed to search it, and Jack nodded and took the other.

“‘He watches over our lady,’” Jack said when we came back together, having pored over every inch of this part of the cathedral. “Could we be misinterpreting it? It doesn’t say that something is here. It says ‘watches over.’ Fitz knows this church. I don’t feel like he’d send us somewhere we can’t look properly.”

A guard walked by, listening to his walkie-talkie, and we got quiet. “Is there a statue that’s watching?” I murmured when he passed. “Or guarding?”

Jack squinted toward the back of the church. “There are a couple paintings that could fit.”

Minutes later, we’d checked paintings of the Crucifixion, of St. Peter curing the sick, of St. Paul preaching to a crowd. Inspected any statue that seemed to be looking down over the nave. Nothing. I fell onto a chair in a multicolored ray of sunlight from a stained-glass window. Jack sat beside me, unbuttoning his blazer. He rested one arm over the back of my chair and one to the other side. He sighed deeply and stared up at the ceiling for just a second before he went back to scanning the church. He never let his guard down for more than a moment.

“Maybe we should try them again,” I said. “We might have missed something.”

“It’s possible,” he conceded, but he showed no signs of getting up again, so I settled into my chair. Jack didn’t move when my shoulder blades rested against his arm, so I didn’t either.

I stared up at the grandeur of the church: tapestries, gold leaf, chandeliers. My eyes kept being drawn to the stained-glass window above us.

“See how there are twelve major sections?” Jack said, jutting his chin at the window I was admiring.

I nodded, counting.

“They represent the twelve families. And just there, in the center? This is one of the only churches in the world to incorporate zodiac symbols.”

“Which there are also twelve of.” I remembered Luc mentioning the Circle’s connection to them.

I’d read my horoscope every morning since I could remember, just for fun. The last one I’d read, on the morning of prom, had said something like, The new moon prompts you to take impulsive action to satisfy your needs. I had had no idea how true that would end up being.

“What’s your sign?” I said. I could see him as a Taurus. The strong, silent type.

“Pisces.” He sat forward and rested his elbows on his knees. “February twenty-third. What’s yours?”

“Hmm. Calm, rational, self-sacrificing. Both emotional and logical,” I said. That actually fit better. It was both sides of him: the poised, proud exterior and the more sensitive parts underneath. “I’m Gemini. June fourteenth.”

“Gemini. Extremely independent.” Jack buttoned and unbuttoned his cuff. “Quick witted. Inquisitive to a fault.” He gave a tiny smile. “Sometimes dual sided or indecisive.”

“Oh really?”

“One of the cooks is into all that astrology stuff,” he said, and I could swear his cheeks got pink.

Astrology buff was not a part of Jack I would’ve expected to find. Especially not the kind of astrology buff who thought I was the dual-sided and indecisive one out of the two of us. Yes, I might have let excitement override caution to come to France in the first place, but I wasn’t the one asking a girl to prom, then making it clear she was just his assignment, then going out of his way to take care of her. Would he have turned me in if we didn’t have Fitz’s clues to follow? Why did I keep caring so much?

But then again, why not? Wrong or not, maybe I could actually admit to myself that I wanted him to care.

We stood up to let a tour group pass in front of us.

“We’d better get back to it,” I said awkwardly. “I wonder if we’re missing something. Like, if ‘watching over’ could mean it’s on the balcony.” I gestured to a second floor that ran the length of the cathedral on both sides. “Is there anything up there?”

“Not artwork or statues, as far as I know.”

A chubby tourist with a camera walked by. “We gotta take a picture of the gargoyles,” he said in a thick Southern accent. “Like in that one movie.”

Jack’s eyes went wide. “The gargoyles. I didn’t like coming to church. Sometimes Fitz would bribe me by promising me we could go up to the bell tower . . . with the gargoyles.” A little smile crossed his face. “We used to joke that one of them looked like a guard dog, like he was watching over the cathedral. Do you think that could be what he meant?”

“If we’re right and these clues are old, it wasn’t him leaving the clue, so I don’t know . . .” I trailed off. “But who knows—he could have been priming you for this for a long time, for all we know. He might have said the guard dog thing just in case. One way to find out.”

Jack offered to go up alone since he’d seen how much I disliked heights, but if we weren’t being chased and there was a solid guardrail, I’d be fine. We passed the gift shop after one flight of stairs, then continued the long trek—444 steps, Jack told me, in a dizzyingly tight spiral—to the top. I was breathing hard by the time we stepped out of the stairwell onto the narrow balcony. A rush of wind cooled the sweat on my face, and all of Paris spread out below us.

A few other tourists leaned out to peer through the wire mesh surrounding the deck like a safety net, and I followed Jack along the balcony. The Seine wound sinuously through the city, and the morning sun glinted off splashes of gold in the distance—the top of a dome here, a rooftop there—and made them stand out from all the cream and gray. Farther away, the Eiffel Tower pierced the haze of the morning.

“There,” Jack said. He pointed down the balcony at one of the gargoyles. A couple about our age cuddled and kissed in front of it while the guy held his phone at arm’s length, snapping pictures.