We let the shark pass, the guards circling us protectively, and though he stared at me with his cold, flat black eyes—for what felt like way too long—in the end he continued on his way without so much as making a move in our direction. Thank God. I don’t think I could have handled a shark attack on top of everything else that was going on right now.

When are you going to get over your silly little fear? Mahina asked when we were once more underway.

When sharks stop ripping things to pieces.

That’s never going to happen.

Precisely my point.

She rolled her eyes at me, but I just ignored her. I didn’t mess with her when she freaked out over octopi. She claimed that she didn’t like the way they looked at her, but really? I’d take an octopus any day of the week over a shark. Unless, of course, it was that horrifically awful thing that attacked my dad.

So it was interesting that, when the attack came, it came not from a shark or an octopus but from the pretty jellyfish that I had always regarded as fairly harmless. Oh, I knew they could sting—you don’t spend your life surfing in tropical climates without suffering a jellyfish sting now and again. But at the same time, I’d never thought of them as particularly fatal until—nearly hallucinatory with exhaustion—we swam straight into a forest of them.

Mahina got stung first. Her cry of pain roused me from my near stupor and I started toward her. I never got there—instead, I ran straight into three jellyfish and got stung on my face, my hand, and my shoulder.

I recoiled in pain and ended up bumping into more jellyfish that had filled in the path behind me. I added more stings, four or five this time, and could feel the venom working its way through my body. My tongue was swelling, my arms and legs were on fire, and I was growing more and more lethargic.

Mahina! Where are you?

I’m over here. She didn’t sound good.

Are you okay?

I can’t—I can’t breathe, Tempest.

Panic ripped through me. Okay, I’m coming for you. Keep talking to me, Mahina.

I’m … trying … I’m … allergic—

Oh, shit. Closing my eyes against the pain, I barreled through the jellyfish between where her voice was coming from and me. I was so focused on getting to her that I barely felt the stings as they happened. At the same time, though, I could feel how the poison was affecting my reflexes—I was slower, more confused, had a hard time keeping my focus.

Mahina, I reminded myself as my mind started to wander. Get to Mahina.

I finally found her. She was drifting through the jellyfish forest, her body horizontal as she moved with the current. I freaked out when I saw her—floating the way she was made her an even bigger target for the jellyfish than if she’d been swimming.

I zipped up to her, grabbed on, and then shot downward into deep, deep water. It took only a minute or so to free ourselves from the jellyfish, but that was a minute filled with a multitude of stings.

Once out, I looked Mahina over. She looked like hell, her face and arms swollen to twice their normal size. Even her tail looked engorged, misshapen, and I knew that we were in trouble.

Mahina! Mahina, don’t go to sleep! You’re better at this stuff than I am. What do I need to do to help you?

Got a shot of epinephrine on you?

No! No, I don’t!

She laughed weakly. Just kidding. Find some kelp. It will help.

Kelp. Got it. I swam around for a full minute like a chicken without her head, freaking out and looking for kelp to just go floating by. Obviously, that didn’t happen. The best place to find it was close to the surface or close to the ocean’s bottom, and we were somewhere in the middle. Of course.

I was scared to bring her deeper, because the water down there was so cold that sometimes it was hard to breathe, even when you were completely healthy. I wasn’t sure what would happen to someone who was already in such bad shape. At the same time, going up was a problem because I didn’t know how big the jellyfish forest was.

Finally, I decided to go down. It seemed the safer bet, since we couldn’t afford for me to get stung any more. I wasn’t allergic, but too much venom and I would be in trouble too.

Mahina, I said, trying to keep her wandering attention on me. I have to go deeper.

Okay, she said in a little singsong voice that sounded like it belonged more to a child than my smart, savvy best friend. We can swim deeeeep!

No! No, you can’t. You have to stay here.

Stay … here, she repeated.

Yes. Here. Please, Mahina. Don’t go anywhere.

I … won’t.

I didn’t trust her, not with the way she was having trouble focusing her eyes. Or the way she was laboring for breath.

Totally freaked out now, I dove deep, swimming as fast as I could. I arrowed straight down, hit the bottom of the ocean about four minutes later. Then nearly cried in relief when I saw a huge seabed of different kinds of kelp. Ignoring the creepiness of the bottom dwellers, I swam over the seabed, grabbing a variety of different plants before heading straight back up to Mahina.

But when I got to where I’d left her, she was gone. I’d been away only ten minutes, but down here that could be an eternity. Especially because I didn’t know if she had taken off swimming or just drifted with the current. Deciding the latter was my better bet, I took off in the same direction the current was flowing, moving fast and scanning the ocean as I went.

Except I couldn’t find her. I went to where I estimated the current would take her; then I went even farther and still, nothing. My chest grew tight and I could feel a panic attack coming on. I couldn’t have lost my best friend. I couldn’t have lost Mahina.

I’d swum far enough to be away from the jellyfish, so I went up and doubled back. No Mahina. Then I dove deep and tried again, zigzagging in an effort to cover as much ground as possible. Still nothing. The panic attack was beginning to take control—no matter how hard I tried to fight it back. What was I going to do? If I couldn’t find her, she would die.

Suddenly, out of the corner of my eye, I saw dim turquoise phosphorescence. For a moment, relief swamped me so completely that I couldn’t move. Couldn’t breathe. And then I was shooting toward the glow, desperate to reach Mahina before she floated away again.

Mahina! I screamed as I approached her. Mahina! Answer me!

Tempest? She sounded far away, even though she was right in front of me.

I found the kelp! What do I do with it? I started putting it on every sting I could find, blanching as I did so. She’d been stung a lot of times.

She watched me blearily. I waited for something to register, waited for the kelp to start working, but nothing was happening. Even worse, her gills were barely working. She was suffocating.

I was out of ideas, but at this point I figured whatever I tried couldn’t hurt. Holding my hands out, I gathered as much electricity as I could from the water around me. It was slow going because we were so deep and the water was cold, really cold, the molecules I was pulling from slow moving and difficult to control.

But I finally figured out how to work with them, and I kept gathering and gathering and gathering until I could feel the white heat of the energy in every part of me. As it spread, I could feel myself getting better—my reflexes getting stronger, the fuzziness dissipating. It gave me hope that I was doing the right thing.

When I was filled with heat, and glowing much more brightly than usual, I took a deep breath and then focused on Mahina. I didn’t want to hit her with too much energy and make her heart stop, but at the same time, I needed to act fast.