I turn and am unable to scream. Unable to move.

A gray fin is coming toward me. And whatever that fin belongs to is huge.

“Delsie!” Ronan is screaming. “Delsie!” And there is a splash. Ronan is in the water coming toward me. The fin is coming my way as well. My brain screams to swim, but I can’t move.

Henry is yelling, too—something I can’t understand over the splashing and the yelling and the fact that I am so terrified.

Ronan swims next to me. He has a buoy. Why?

“Ronan! Be careful!” I yell.

He faces the fin, looking like he’s ready to fight.

I finally make out that Henry is yelling, “It’s okay! It’s okay!”

There is nothing okay about this.

We watch as the fin circles. The shark is wide and round. It’s enormous.

Henry is yelling still. “It’s a sunfish. It won’t hurt you. It’s a sunfish. It’s okay. It won’t hurt you.”

Wait. What?

I turn and look again. Henry is cupping his hands around his mouth to be louder. “Look at the fin. Floppy on top. It’s not a shark.”

Ronan lets out a gasp, and so do I. We laugh with relief as the enormous, goofy-looking fish with the floppy fin circles us. Curious, I guess.

“I thought you knew everything about sharks!” I say.

“Well, I know a lot about sharks, but I don’t know anything about sunfish! I thought the fin was weird, but I panicked just based on its size. It’s huge!”

I point at the buoy in his hand. “What did you bring that for?”

“If you hit a great white in the eyes, it sends them off.”

“But you love great whites,” I tease him. “You would hit one for me?”

“Duh, what do you think?”

When we are back on the boat, Henry shakes his head. “You’re an impressive kid, Ronan. You really are. But even you couldn’t beat a great white.”

“I was going to punch him in the eyes or the gills with the buoy. That stuns them. They’ll swim away if you hit them hard and in the right place. I’ve read all about it in books.”

“Written by someone with no arms. Or worse.”

“They’re fighters,” Ronan says.

“Yeah, and some fighters it’s probably best not to mess with.” Henry looks at me. “You know which animal in the ocean is a real fighter? And your mom’s favorite, Delsie?” he says, pointing at the ring on my finger. “The sperm whale.”

I touch the whale with my fingertip. “She liked them that much? Why?”

“Because they fought back when whalers harpooned them. Right in these very waters, actually. Back in the 1800s. Now, the other types of whales? Well, they’d die pretty conveniently once the harpooner stuck ’em. But the sperm whale . . . it crashed boats into toothpicks. Pulled boats across the sea at high speed bouncing over the waves. Men hanging on for their lives. They’d even pull the boats underwater. That was called the Nantucket sleigh ride. And it was deadly for men.”