“Cannonball!” Taylor yells, and hurls herself into the air, arms wrapped around her knees. The next second there’s a gigantic splash that temporarily blinds me. Crossly wiping my eyes and blinking, I see water pouring over the edge of the pool and running into the channel cut into the marble drainage surround. Shock waves from the impact lap around me; it feels as if Taylor’s displaced half the water in the swimming pool.

I’m not in the mood for cannonballs. To be honest, Taylor’s obsession with them is annoying me. I’m still pretty depressed about the fact that I thought I was getting close to solving Dan’s murder, and now I’m back to square one again. It’s okay for Taylor, because it isn’t personal to her. But this means everything in the world to me, and I’ve just been dealt a crushing blow. I really think Taylor could be a bit more sympathetic. Instead, she isn’t even noticing that I’m paddling around in the shallow end, dispirited and listless. She’s hauling herself out of the water again for another cannonball instead. I turn away so I don’t get a faceful of water this time.

“Cannonball!” she yells again, just before another half-ton of water shoots out of the pool in her wake.

I suppose it’s not her fault that investigating Dan’s death just isn’t as important to her as it is to me. For Taylor it’s something to do to relieve the crushing boredom of life at Wakefield Hall Maximum Security Prison, and, of course, a great opportunity to train up in those PI skills she wants to improve. And sometimes she forgets that to me, this is much more than just a way to kill time. I mop the spray from her impact out of my hair and reflect that, in the end, I’m the only person I can truly rely on a hundred percent. That’s only normal, I suppose. We’re all alone in the end.

But I hate acknowledging it.

Suddenly, watching Taylor cavort around in the deep end, a deep rush of loneliness washes over me. Am I over-relying on her? Maybe I am, if the fact that she’s not focusing on this disappointment as much as I am is upsetting me this much. Perhaps I need to lean less on Taylor and stand more on my own two feet. I was so happy to make friends with her because when I met her my old friends had dumped me (my own fault, so I shouldn’t really complain). Taylor doesn’t have anyone else either: she’s as much an outsider at Wakefield Hall as I am. After some initial mistrust and hostility, it’s amazing how quickly we’ve bonded. But have I rushed things too much? Do I need to get more balance in my life and not assume that Taylor will always be there for me?

Ugh, too many questions, and all of them miserable. I dive underwater to shake them off, swimming slowly along the bottom of the shallow end, wishing I could stay down here forever and never have to come up to face the problems on the surface.

Believe it or not, we’re in the basement of Lizzie’s house. Which, besides the heated swimming pool, has a private cinema, game room, and, for all I know, a bowling alley and tennis court as well. When we realized we would have to stay in London tonight—because we couldn’t go out late to a club Saturday night and get back to school at two in the morning—Lizzie offered to put us up. It took us both by surprise, as, to be honest, we haven’t really been that nice to her. But she was quite excited by the idea.

“Lizzie doesn’t really have any friends, does she?” Taylor said earlier. “When I asked Mademoiselle Fournier if I could stay over at Lizzie’s tonight, she sounded happier that Lizzie had someone to stay with than that I had someone to visit.”

“Honestly, I could have told my aunt Gwen I was staying with a pedophile I met when he picked me up in the knickers section of Marks and Spencer’s, and she wouldn’t have batted an eyelid,” I said sourly.

“Yeah, but your aunt Gwen hates you,” Taylor pointed out with brutal frankness.

“She doesn’t think much of Lizzie, either. She sniffed when I said who I was staying with. And when I said she was a friend of ours, I know she didn’t believe me.”

Taylor shrugged. “Well, maybe we’re the closest she’s got.”

“That’s pretty sad. We should be nicer to her.”

Taylor pretended to gag, but beneath that tough exterior is a slightly—slightly—softer heart, and she was actually quite polite to Lizzie this afternoon as Lizzie proudly showed us to our rooms. (Yup, we have one each, and they’re huge, and they’re both en suite. All this in Chelsea, the most expensive area in the whole of London. Lizzie’s dad clearly has more money than God.)

We didn’t realize there was a swimming pool, though. Lizzie was too absorbed in showing us her built-in handbag and shoe cupboards, plus her wet room and Jacuzzi. We found that out from Lucia, the Romanian live-in housekeeper, who let us in when we got back from the club.

“You want something to eat?” she asked, stone-faced, when we’d finished apologizing for making her get up to let us in. (“Is okay. Is my job. Miss Lizzie say perhaps you not come back with her.”)

“No, that’s fine,” I said wistfully, kicking Taylor, who always wants something to eat. But I knew if we said yes, Lucia would have to get it for us, and she had clearly got out of bed to let us in—she was in her dressing gown and slippers, and her eyes were all blurry with sleep.

“You have drink?” Lucia asked. “Watch film in cinema? Swim?”

“I’m sorry,” I said blankly, “I must have misheard you, but I thought you said  .  .  .”

Five minutes later the lift doors pinged open, and Lucia led us out and down a beautifully tiled corridor. She pushed open a door. We gasped.

“Hot towels there. Swimming clothes there. Sauna there,” she pointed, though we were too mesmerized by the delicate cloud of steam rising off the bright blue water of the swimming pool to really focus on her directions. “Toilet also.” She indicated the far side of the pool, which is set in pale pink–tinged marble. “Behind the pillars.” Those were marble too, of course.

“Thank you so much,” Taylor said fervently.

“No problem.” Lucia actually cracked a tiny smile. “You good girls. Not drunk. I not smell drink when you talk.”

“Um, thank you,” I said, profoundly grateful we hadn’t had a cocktail in Coco Rouge.

Lucia turned to leave.

“You drink water now,” she said over her shoulder. “For the sauna.”

“Yes, Lucia,” we chorused.

I surface from my underwater swim, wishing my aunt Gwen were more like Lucia. I don’t mind a bit of tough love. And Lucia was nicer to me than Aunt Gwen’s been my whole life.

“Show me how you spin round so fast in that somersault you do on the trampoline,” Taylor calls, pulling herself out of the pool with one smooth flex of her powerful upper body.

“I’m not really feeling like it,” I mumble, treading water.

“Oh, come on, Scarlett!” Taylor puts her hands on her hips. “I know tonight was disappointing, but we’re in a private swimming pool—that’s got to cheer you up a bit!”

Now I feel like I’m being a misery guts, and dragging Taylor down with me. Guiltily, I instruct her:

“You need to get into the tuck as fast as you can. Snap your arms down like you’re throwing a ball, and by the time they come down, your knees should be tucked tight into your chest.”

“Throwing a ball,” Taylor says, raising her arms above her head and trying it out. “Okay, here I go!”

She runs toward the edge of the pool, jumps up, tucks up, and in that precise moment a voice booms out from nowhere, bouncing round the tiles and marble so loudly that Taylor’s tuck somersault goes completely haywire.

“Are you in the pool?” the voice says.

Taylor throws out her arms wide, I don’t know why, but it completely stops her spin, and she lands facedown in the pool, her arms splayed wide and her knees still tucked up to her chest. I laugh so hard I double up. The expression of total shock when she comes up again makes me laugh even harder. And I don’t even feel bad about laughing at her. After all, not a minute ago she was lecturing me about needing to cheer up.

“Are you in the pool?”

“Aaaah!” Taylor gasps for breath, coughing out water. To my shame, this is somehow even more funny than the belly flop. Maybe it’s because I’ve never seen Taylor be anything but in complete physical control of herself.

“Are you in the pool?” the voice asks again.

“Who the hell are you?!” Taylor shouts back. Her face is bright red: she’s literally livid.

“It’s Lizzie!”

“Stop screaming at us!” Taylor yells.

“Sorry, it’s the intercom! It makes everything sound really loud! I’m coming down!”

Lizzie bursts through the door a few minutes later, all excited. I bet Lucia would have smelled drink on her breath.

“Hey!” she says, beaming. “Are you enjoying the pool? Isn’t it great? And what about that scene in the club! Wasn’t it crazy? Plum had a complete meltdown! I was scared, but it was really exciting, too! And how did your top-secret mission go? Did you find everything out?”

“Not really,” I say, sighing. “It turned out to be much more complicated than we realized.”

“Oh, that’s a shame!” Lizzie actually looks disappointed on our behalf. “I know, why don’t I make some popcorn? And we can have cocoa with mint Baileys and marshmallows in it? That’s my favorite!” She claps her hands in glee, like a little girl. “I’ll go and start the popcorn machine. Meet you in my living room. Take the lift to the third floor and turn left, all the way down the corridor. Ooh, this is going to be so much fun!”

“I never thought these words would come out of my mouth,” Taylor says as the door bangs shut behind Lizzie, “but I gotta say, sometimes being Lizzie’s friend seems like a really good deal.”

Naturally, the pool changing room is well stocked with fluffy toweling robes and assorted spa-type slippers, so ten minutes later we’re curled up in front of a roaring fire in Lizzie’s sitting room, mugs of hot, minty, and slightly alcoholic cocoa in our hands, a bowl of popcorn between us, and the very comforting popping sound of another batch cooking up in the machine. This is the life.

Or it would be, if I weren’t feeling, very strongly, that tight little knot inside my stomach, which is the perpetual reminder I have of Dan’s death. That knot’s always with me, but sometimes I don’t feel it as much as others. Right now, it’s like a stone in my stomach, hard and cold, because I’m so disappointed about tonight.

But also, I’m really enjoying this coziness, and my cocoa is so delicious it’s competing with the tight knot for attention. It’s weird feeling torn like this.

That’s another reason I’m so keen to solve Dan’s murder. I want to be able to feel just one feeling at a time. I want to get rid of the stone in my stomach.

“I feel like we’re in a ski resort in Colorado,” Taylor comments, blowing on her drink.

“It’s cozy, isn’t it?” Lizzie beams. “Sometimes I make my cocoa and take it into the Jacuzzi to watch TV. That’s lovely too, though you can’t see the fire. So what was the problem tonight?” she continues, so happy to feel she’s at the center of something that her eyes are shining like headlights.

Here’s the thing: we can’t tell Lizzie anything important, as she’ll just babble it to everyone she knows in an effort to show off how she’s in our confidence. She knows, of course, that something’s going on between us and Nadia, something secret and complicated and important. Still, everyone involved has kept her completely in the dark. But Taylor and I had a quick brainstorm downstairs, and we decided that there was one issue on which Lizzie might actually be helpful. It’s her special subject, after all.

I sigh. “It sounds silly,” I say, “but Nadia wanted our help. You see, there’s a boy she likes, and she thinks he likes her. Only she’s not sure. And a few nights ago, they were out at a club, and she was sitting with Plum’s handbag next to her—”

“The Marc Jacobs limited edition!” Lizzie interrupts excitedly, eager to show off that she knows Plum’s wardrobe.

“Exactly. And she thinks this boy thought it was her bag—Nadia’s, that is—and put in a note for her.”

This part of the story is very weak indeed. I mean, who leaves notes nowadays? I keep talking quickly before Lizzie starts to realize it doesn’t quite make sense.

“Only the thing is, it wasn’t Plum’s bag after all—she got confused, ’cause quite a few girls have the same bag, apparently, but she didn’t realize. So she really wants to find out who’s got the same bag and see if any of them got a note in it that wasn’t meant for them.”

I look dubiously at Lizzie: is she actually falling for this? I didn’t have time to come up with a better story. Luckily, the cocktails at Coco Rouge and the Baileys have dissolved any shred of common sense she might have possessed.

“That’s so romantic!” she breathes. “And now he doesn’t know that she didn’t get the note, so he might think she doesn’t like him.  .  .  . It’s sort of like Romeo and Juliet, isn’t it?”

“Um, yeah,” I say, tilting my head to one side and trying to make my eyes go misty. This also means I avoid catching Taylor’s eye, which I don’t think will be a good idea if I want to keep being convincing. I leave it a moment, then say thoughtfully:

“I don’t suppose you have any idea who else has that bag, do you?”

Lizzie almost jumps up and down in glee, her Baileys cocoa slopping dangerously near the edge of her mug.

“Of course I do!” she says excitedly. “Sophia has one! She only got it last month, her sister gave it to her because she was bored with it, but Sophia really likes it, she takes it everywhere, even if it doesn’t really go with what she’s wearing.  .  .  .”

“Sophia Von und Zu Whatsit?”

“Yes, it’s funny, because you know how Plum hates it when people have the same thing as her, it’s sort of a rule that you don’t have anything the same, right? But Sophia really, really wanted to keep the bag, and apparently, when she came into school with it”—Lizzie puts down her mug and leans forward in her velvet armchair, all excited to be telling us what she considers a prime piece of gossip—“she put it under her chair so Plum didn’t see it straightaway. And then Sophia invited Plum that morning to come to their schloss with them for half-term. Which is amazing, apparently, it’s like an entire castle in Austria and it looks like something out of a fairy tale, and Sophia’s family are really, really posh and fantastically well-connected, so Plum’s been dying to get an invitation there for ages. So of course she said yes. And then Sophia reached down to get her bag and everyone saw it for the first time. And apparently, everyone went absolutely dead silent, but Sophia had just invited Plum to stay, so Plum didn’t, you know, do anything about it. It was sort of like a bargain, know what I mean?”

“Yeah, I do. Okay, so Sophia has one,” I prompt. “Does anyone else have the same bag?”

Lizzie’s nodding vigorously. “Lucy has one. Lucy Raleigh.” Lizzie’s eyes go moony and puppylike, the way they do when she mentions Plum’s name. Which is interesting, because I’ve never seen Lizzie look like this about anyone but Plum.

“Who’s Lucy Raleigh?” Taylor asks.

“You don’t know?” Lizzie is incredulous. “She’s, like, incredibly pretty and cool. She’s at St. Paul’s Girls’. She was at the club tonight, did you see her? She was wearing a D&G top and Made by Lou jeans”—she stops for a moment, narrowing her eyes—“and,” she finishes triumphantly, “a Guess jacket. I think it was Guess,” she adds conscientiously. “I think she was the first person to have one of those bags. I haven’t seen her with it for ages, though.”

Sophia was at the party when Dan died, but that was six months ago, and according to Lizzie’s story, her sister only recently gave her the bag. So she’s in the clear. I must say, I’d have found it very hard to believe that Sophia had anything to do with killing Dan. I used to be in the same history class as her at St. Tabby’s, and as a result, I know that Sophia has about as many brain cells as a newt. Organizing anything that complicated would be out of the question for her—the mental strain would put her in a coma for weeks.

“And no one else has one of those bags?” Taylor asks.

Lizzie shakes her head. “No one we know. They didn’t make that many.”

Well, that’s definite. If there’s one subject Lizzie’s an expert on, it’s handbags.

Suddenly, the coziness of Lizzie’s sitting room turns suffocating. I’ve got a clue.

Taylor’s eyes are gleaming: I can see she feels exactly the same. Lucy Raleigh. Who goes to St. Paul’s Girls’. And is incredibly pretty and cool. Could she have anything to do with Dan’s murder?

Oh, there’s one more thing to clear up.

“Does Sophia’s sister hang out with Plum’s lot at all?” I ask, just to make sure there’s no chance that the sister was at Nadia’s party.

Lizzie looks amazed. “God, no! She’s much older. She’s, like, married!”

Well, that rules the sister out, which means we can completely concentrate on this Lucy Raleigh. My mood is improving by the moment: we have a real clue here to focus on. And in the taxi, I talked myself out of real suspicions of Plum. Maybe I’m wrong, but thinking it over, I do have my doubts that it’s in Plum’s character to carry out such a complicated and sneaky plot. Plum’s all about direct confrontation. Maybe, if I find out more about Lucy Raleigh, it’ll turn out that she’s much more the type to kill someone in the kind of way Dan was murdered.  .  .  .

“So you think that maybe Lucy got the note that was meant for Nadia?” Lizzie’s asking.

Our blank expressions would completely expose us for total liars, if it weren’t Lizzie we were dealing with. We really have to work on our reflexes if we want to be super–spy girl detectives.

“Yeah!” I say, several beats too late, as Taylor chimes in with an overenthusiastic series of nods.

“Oh, I hope she gets together with him,” Lizzie sighs wistfully. “It sounds incredibly romantic!”