I don’t want to even imagine the type of creature that’s living inside. At the basin of the crater, the radiation will be high, meaning whatever lives down here will have taken a huge dose over the years. Just like the crazies in the lakes in the north, the creatures living down here will have evolved into something unrecognizable and formidable.

We all agree it’s too risky to venture into the burrow, even if it does eventually lead out of the crater. If there is something sleeping inside, it’s probably best to let it rest.

“I think I see something,” Ben says, peering into the distance.

Sure enough, there’s another path leading up the crater, made by the same prints as the one we took down. The animals that made these tracks have shown us down into the crater and are now offering us a way back out. They’re like guardian angels.

We go back to get the bikes and head toward the path. But as we go, a new noise joins the thrumming of our engines.

Jack and Penelope are suddenly alert, their ears pricking up, their teeth bared.

“What’s that noise?” I call out to the others.

We draw to a halt and cut off the engines. As soon as we do, the noise becomes perceptible. There’s no mistaking it. It’s the howling of wolves. And it’s close. Too close for comfort.

Penelope and Jack immediately join in with the howling. Bree tries to quiet Penelope down but it’s no use. The tiny Chihuahua is trying to make herself look fierce.

“Quick,” I say. “We have to go.”

But it’s too late. All at once, we’re surrounded by the most disgusting creatures I’ve ever seen. They look like wild dogs, but the radiation they’ve absorbed from having lived in the crater has made their bodies mangled. Their spines are curved upward, making them look more like hyenas than dogs. Their fur is balding in places, sticking up coarsely in others. Tumors grow out of their skin. Saliva drips from their jaws in thick strings, and their teeth, like their claws, are enormous.

I gun the engine of my bike, hoping that the noise will scare them off, and start whizzing around and around in circles, trying to tire the creatures out so that they’re slow enough to take a hit. The others do the same. The wolves chase our bikes, their eager jaws snapping, treating it like a game, as though they’re nothing but puppies. It reminds me of Sasha, our old pet dog, and the way she would lumber around play fighting with me. I’m almost relieved that she was killed by slaverunners; they saved her from this fate, of being turned into a grotesque, cancerous, murderous creature.