Now, maybe I've seen the movie Jaws one too many times, but I have always made it a point never to wade farther than waist-deep into the ocean - any ocean. So when I found myself surging toward the spot where I'd last seen Michael, and felt the sand shelf I'd been running on give out beneath me, I tried to tell myself that the lurch my heart gave was one of adrenaline, not fear.

I tried to tell myself that, of course. But I didn't believe me. When I realized I was going to have to start swimming, I completely freaked. I swam, all right - I know how to do that, at least. But the whole time I was thinking, Oh, my God, please don't let anything gross, like an eel, touch me on any part of my body. Please don't let a jellyfish sting me. Please don't let a shark swim up from underneath me and bite me in half.

But as it turned out, I had way worse things to worry about than eels, jellyfish, or sharks.

Behind me, I could hear voices shouting dimly. Gina and Cee Cee and Adam, I figured, in the part of my brain that wasn't paralyzed with fear. Yelling at me to get out of the water. What did I think I was doing, anyway? The lifeguard had the situation well in hand.

But the lifeguard couldn't see - or fight - the hands that were pulling Michael down.

I saw the lifeguard - who had no idea, I'm sure, that some crazy girl had dove in after him - let the enormous wave approaching us gently lift his body and propel him that much closer to where Michael had disappeared. I tried his technique, only to end up sputtering, with a mouthful of saltwater. My eyes were stinging, and my teeth starting to chatter. It was really, really cold in the water without a wetsuit.

And then, a few yards away from me, Michael suddenly resurfaced, gasping for breath and clawing at the rope of seaweed around his neck. The lifeguard, in two easy strokes, was beside him, shoving the orange flotation device at him, and telling him to relax, that everything was going to be all right.

But everything was not going to be all right. Even as the lifeguard was speaking, I saw a head bob up beside Michael. Though his wet hair was plastered to his face, I still recognized Josh, the ringleader of the RLS Angels - a ghostly little group so hellbent on mischief making … and evidently worse.

I couldn't speak, of course - my lips, I was sure, were turning blue. But I could still punch. I pulled my arm back and let go of a good one, packed with all the panic I felt at finding myself with nothing but water beneath my feet.

Josh either didn't remember me from Jimmy's or the mall, or didn't recognize me with my hair all wet. In any case, he'd been paying no attention to me at all.

Until my fist connected solidly with his nasal cartilage, that is.

Bone crunched quite satisfyingly under my knuckles, and Josh let out a pain-filled shriek that only I could hear.

Or so I thought. I'd forgotten about the other angels.

At least until I was abruptly pulled under the waves by two sets of hands that had wrapped around my ankles.

Let me just mention something here. While to the rest of humanity, ghosts have no actual matter - most of you walk right through them all the time and don't even know it; maybe you feel a cold spot, or you get a strange chill, like Kelly and Debbie did at the convenience mart - to a mediator, they are most definitely made of flesh and bone. As illustrated by my slamming my fist into Josh's face.

But because they have no matter where humans are concerned, ghosts must resort to more creative methods of harming their intended victims than, say, wrapping their hands around their necks. It was for that reason that Josh was using seaweed instead. He could pick up the seaweed - with an effort, like the beer in the Quick Mart. And he could wrap that around Michael's neck. Mission accomplished.

I, on the other hand, being a mediator, was not subject to the laws governing human-ghost contact, and, accordingly, they quickly made use of their unexpected advantage.

Okay, I realized then that I had made a bad mistake. It is one thing to fight bad guys on land, where, I must admit, I am quite resourceful, and - I feel I can say without bragging - quite agile.

But it is quite another thing altogether to try to fight something underwater. Particularly something that does not need to breathe as often as I do. Ghosts do breathe - some habits are hard to break - but they don't need to, and sometimes, if they've been dead long enough, they realize it. The RLS Angels hadn't been dead very long, but they'd died underwater, so you might say they had a head start on their spectral peers.

Given those circumstances, I saw my situation progressing in one of either of two ways: either I was going to give up, let my lungs fill with water,. and drown, or I was going to completely freak out, strike at anything that came near me, and make those ghosts sorry they'd ever chosen not to go into the light.

I don't suppose it will come as any big surprise to anyone - with the exception of myself, maybe - that I chose the second option.

The hands that were wrapped around my ankles, I realized - though it took me a while; I was pretty disoriented - were connected to bodies, attached to which, presumably, were heads. There is nothing so unpleasant, I know from experience, as a foot to the face. And so I very promptly, and with all my strength, kicked in the direction that I supposed those faces might be, and was gratified to feel soft facial bones give way beneath my heels.

Then with my arms, which were still free, I gave a mighty stroke, and broke back through the water's surface, gulping in a huge lungful of air - and checking to make sure Michael had gotten well and truly away, which he had; the lifeguard was towing him back to shore - before I dove down again, in search of my attackers.

I found them easily enough. They were still in their prom wear, and the girls' dresses were floating all around them like seaweed. I grabbed a handful of one, tugged it toward me, and saw, in the murky water, the very startled face of Felicia Bruce. Before she had a chance to react, I plunged a thumb into her eye. She screamed, but since we were underwater, I didn't hear a thing. I just saw a trail of bubbles racing for the water's surface.

Then someone grabbed me from behind. I reacted by thrusting my head back, as hard as I could, and was delighted to feel my skull make very hard contact with my attacker's forehead. The hands that had been holding me instantly let go, and I spun around, and saw Mark Pulsford swimming hastily away. Some football player he'd been, if he couldn't take a simple head butt.

I felt the urgent need to breathe, so I followed the last of the bubbles from Felicia's scream, and resurfaced just as the ghosts did, too.

We all bobbed there on the surface: me, Josh, Felicia, Mark, and a very white-faced Carrie.

"Omigod," Carrie said. Her teeth, unlike mine, weren't chattering. "It's that girl. That girl from Jimmy's. I told you she can see us."

Josh, whose broken nose had sprung, cartoon-like, back into place, was nevertheless wary of me. Even if you happen to be dead, getting your nose broken hurts a lot.

"Hey," he said to me as I treaded water. "This isn't your fight, okay? Stay out of it."

I tried to say, "Oh, yeah? Well, listen up. I'm the mediator, and you guys have a choice. You can go on to your next life with your teeth in or your teeth out. Which is it going to be?"

Only my own teeth were chattering so hard, all that came out was a bunch of weird noises that sounded like, Oah? Esup. Imameator an -

You get the picture.

Since Father Dominic's technique - reasoning - didn't appear to be working in this particular instance, I abandoned it. Instead, I reached out and grabbed the rope of seaweed they'd tried to strangle Michael with and flung it around the necks of the two girls, who were treading water close to each other, and to me. They looked extremely surprised to find themselves lassoed like a couple of seacows.

And I can't really tell you what I was thinking, but it's probably safe to say my plan - though somewhat haphazardly formed - involved towing them both back to shore where I intended to beat the crap out of them.

While the girls clawed at their necks and attempted to escape, the boys came at me. I didn't care. I was furious all of a sudden. They had ruined my nice time at the beach and tried to drown my date. Granted I wasn't particularly fond of Michael, but I certainly didn't want to see him drowned before my eyes - particularly not now that I knew what a hottie he was under his sweater vest.

Holding onto the girls with one hand, I thrust out the other and managed to grab Josh by - what else? - the short hairs on the back of his neck.

Though this proved highly effective - in that he promptly began thrashing in pain - I'd neglected two things. One was Mark, who continued to swim free. And the other was the ocean, which was still churning waves at me. Any sensible person would have been looking out for these things, but I, in my anger, was not.

Which was why a second later, I was promptly sucked under.

Let me tell you, there are probably pleasanter ways to die than choking on a lungful of saltwater. It burns, you know? I mean, it is, after all, salt.

And I coughed down a lot of it, thanks first to the wave, which bowled me under. And then I swallowed a lot more when Mark grabbed hold of my ankle, and kept me under.

One thing I have to admit about the ocean: it's very quiet down there. I mean, really. No more shrieking gulls, crashing of the waves, shouts from the surfers. No, under the sea, it's just you and the water and the ghosts who are trying to kill you.