Willem reaches into his pocket, pulls out a fistful of foreign currencies. “Don’t worry about that. It was a good summer.”

I stare at the bills in his hand. Would he really do that? Take me to Paris? Why would he do that?

“We have tickets for Let It Be tomorrow night,” Melanie says, assuming the Voice of Reason. “And we’re leaving on Sunday. And your mom would freak out. Seriously, she’d kill you.”

I look at Willem, but he just shrugs, like he cannot deny the truth to this.

And I’m about to back down, say thanks for the offer, but then it’s like Lulu grabs the wheel, because I turn to Melanie and say, “She can’t kill me if she doesn’t find out.”

Melanie’s scoffs. “Your mom? She’d find out.”

“Not if you covered for me.”

Melanie doesn’t say anything.

“Please. I’ve covered for you plenty on this trip.”

Melanie sighs dramatically. “That was at a pub. Not in an entirely different country.”

“You just criticized me for never doing things like this.”

I have her there. She switches tacks. “How am I supposed to cover when she calls my phone looking for you? Which she’ll do. You know she will.”

Mom had been furious that my cell phone didn’t work over here. We’d been told it would, and when it didn’t, she called the company up in a tizzy, but apparently there was nothing to be done, something about it being the wrong band. It didn’t really matter in the end. She had a copy of our itinerary and knew when to get me in the hotel rooms, and when she couldn’t manage that, she called Melanie’s cell.

“Maybe you could leave your phone off, so it goes to voice mail?” I suggest. I look at Willem, who still has the fistful of cash spilling out of his hand. “Are you sure about this? I thought you were going back to Holland.”

“I thought so too. The winds are maybe blowing me in a different direction.”

I turn to Melanie. It’s on her now. She narrows her green eyes at Willem. “If you rape or murder my friend, I will kill you.”

Willem tsk-tsks. “You Americans are so violent. I’m Dutch. The worst I will do is run her over with a bicycle.”

“While stoned!” Melanie adds.

“Okay, maybe there’s that,” Willem admits. Then he looks at me, and I feel a ripple of something flutter through me. Am I really going to do this?

“So, Lulu? What do you say? You want to go to Paris? For just one day?”

It’s totally crazy. I don’t even know him. And I could get caught. And how much of Paris can you see in just one day? And this could all go disastrously wrong in so many ways. All of that is true. I know it is. But it doesn’t change the fact that I want to go.

So this time, instead of saying no, I try something different.

I say yes.

The Eurostar is a snub-nosed, mud-splattered, yellow train, and by the time we board it, I am sweaty and breathless. Since saying good-bye to Melanie and hastily exchanging plans and info and meeting places for tomorrow, Willem and I have been running. Out of Marylebone. Down the crowded London streets and into the Tube, where I got into some sort of duel with the gates, which refused to open for me three times, then finally did, before snapping shut on my suitcase, sending my Teen Tours! baggage tag flying underneath the automatic ticket machine. “I guess I’m really going rogue now,” I joked to Willem.

At the cavernous St. Pancras station, Willem pointed out the destination boards doing that shuffling thing before hustling us to the Eurostar ticket lines, where he worked his charm on the ticket agent and managed to exchange his ticket home for a ticket to Paris and then used far too many of his pound notes to buy me mine. Then we rushed through the check-in process, showing our passports. For a second, I was worried that Willem would see my passport, which doesn’t belong to Lulu so much as to Allyson—not just Allyson, but fifteen-year-old Allyson in the midst of some acne issues. But he didn’t, and we went downstairs to the futuristic departure lounge just in time to go back upstairs to our train.

It’s only once we sit down in our assigned seats on the train that I catch my breath and realize what I’ve done. I am going to Paris. With a stranger. With this stranger.

I pretend to fuss with my suitcase while I steal looks at him. His face reminds me of one of those outfits that only girls with a certain style can pull off: mismatched pieces that don’t work on their own but somehow all come together. The angles are deep, almost sharp, but his lips are pillowy and red, and there are enough apples in his cheeks to make pie. He looks both old and young; both grizzled and delicate. He’s not good-looking in the way that Brent Harper, who was voted Best Looking in the senior awards, is which is to say predictably so. But I can’t stop looking at him.

Apparently I’m not the only one. A couple of girls with backpacks stroll down the aisle, their eyes dark and drowsy and seeming to say, We eat sex for breakfast. One of them smiles at Willem as she passes and says something in French. He replies, also in French, and helps her lift her bag into the overhead bin. The girls sit across the aisle, a row behind ours, and the shorter one says something, and they all laugh. I want to ask what was said, but all at once, I feel incredibly young and out of place, stuck at the children’s table for Thanksgiving.

If only I’d studied French in high school. I’d wanted to, at the start of ninth grade, but my parents had urged me to take Mandarin. “It’s going to be the Chinese century; you’ll be so much better able to compete if you speak the language,” Mom had said. Compete for what? I’d wondered. But I’ve studied Mandarin for the last four years and am due to continue next month when I start college.

I’m waiting for Willem to sit down, but instead he looks at me and then at the French girls, who, having deposited their things, are sashaying down the aisle.

“Trains make me hungry. And you never ate your sandwich,” he says. “I’ll go to the café for more provisions. What would you like, Lulu?”

Lulu would probably want something exotic. Chocolate-covered strawberries. Oysters. Allyson is more of a peanut-butter-sandwich girl. I don’t know what I’m hungry for.

“Whatever is fine.”

I watch him walk away. I pick up a magazine from the seat pocket and read a bunch of facts about the train: The Channel Tunnel is fifty kilometers long. It opened in 1994 and took six years to complete. The Eurostar’s top speeds are three hundred kilometers per hour, which is one hundred and eighty-six miles per hour. If I were still on the tour, this would be exactly the kind of Trivial-Pursuit fodder Ms. Foley would read to us from one of her printouts. I put the magazine away.

The train starts to move, though it’s so smooth that it’s only when I see the platform is pulling away from us, as though it’s moving, not the train, that I realize we’ve departed. I hear the horn blow. Out the window, the grand arches of St. Pancras glitter their farewell before we plunge into a tunnel. I look around the car. Everyone else seems happy and engaged: reading magazines or typing on laptops, texting, talking on their phones or to their seatmates. I peer over my seat back, but there is no sign of Willem. The French girls are still gone too.

I pick up the magazine again and read a restaurant review that I don’t absorb at all. More minutes tick by. The train is going faster now, arrogantly bypassing London’s ugly warehouses. The conductor announces the first stop, and an inspector comes through to take my ticket. “Anyone here?” he asks, gesturing to Willem’s empty seat.

“Yes.” Only his things aren’t there. There’s no evidence he ever was here.

I glance at my watch. It’s ten forty-three. Almost fifteen minutes since we left London. A few minutes later, we pull into Ebbsfleet, a sleek, modern station. A crowd of people get on. An older man with a briefcase stops next to Willem’s seat as if to sit there, but then he glances at his ticket again and keeps moving up the aisle. The train doors beep and then shut, and we are off again. The London cityscape gives way to green. In the distance, I see a castle. The train greedily gobbles up the landscape; I imagine it leaving a churned-up pile of earth in its wake. I grip the armrests, my nails digging in as if this were that first endlessly steep incline up one of those lunch-losing roller coasters that Melanie loves to drag me on. In spite of the blasting AC, a line of perspiration pearls along my brow.