“What’s the matter, Mabel?” her husband asks with a laugh. Her throwing arm slowly swings down and she drops the beanbag on the ground. “That’s a balk. Runners, advance.” Then he stops laughing as she goes limp and slack-jawed, and her whole body turns to cellular Silly Putty. “Mabel? Oh my God! Someone call a doctor!”

The cyborg re-aims. Gisco and I stay low, scuttling around rides as we try to keep him from getting a clear shot. But he’s stalking us skillfully, and we’re running out of cover. I hear a bell ringing. “Gisco! The Death Coaster is setting off!”

I’d rather have my axons blasted, the dog declares.

“Suit yourself,” I tell him, and sprint toward the nearby tracks. The roller-coaster cars rumble by, starting to gather speed for a long climb. I vault the rail and jump into an empty seat.

“Hey,” a boy behind me yells, “you can’t do that.”

“I’ll pay when it’s over,” I tell him.

A second later Gisco hurtles over the rail and crash-lands next to me on top of the safety bar. You’re right, this is the only way out. But how does this safety bar open?

It’s already locked down. Just hold on tight.

Dogs don’t have fingers!

That evolutionary failing may cost you dearly.

Gisco takes this personally. As Darwin would no doubt explain to you, dogs occupied a vital niche in the survival of the fittest and paws were a significant advancement … He ends his learned discourse as we stop climbing skyward and sit for a second looking down at an impossibly steep descent. Jack, I can’t hold on! I’m going to die!

What were you just saying about paws?

The terrified dog jumps into my lap. You hold on to me!

Impossible, old fellow. I need both hands to grip the bar.

What am I supposed to do?

Darwin would probably suggest you adapt.

Gisco looks around wildly, but there’s no one else to help him and nothing to be done. As our car begins accelerating downward, he locks his massive jaws around the safety bar.

We plummet earthward. All around me, kids bellow in joyous fear. I hold on for all I’m worth, and glance at the dog.

He now seems to be flying above our car, inverted, like a furry guardian angel. He’s literally clinging to the safety bar, and to life itself, by the skin of his canines. Enjoying the Death Coaster, Gisco?

I’ll get you back for this. Fingers can be gnawed off in ten bites.

Hold tight, Gisco. Here come the death spirals.

The speed we have built up from our plunge keeps the cars pinned with centrifugal force as we are spun upside down and whipped through five loops.

Blood rushes to my head. My fingers probably leave marks in the steel bar. I’ve never liked roller coasters.