A refrigerator truck.

This was nothing, I said to myself. Nighttime yogurt delivery; pork link sausages for breakfast, freshness guaranteed. A load of grouper headed north or to the airport. Refrigerated trucks moved through Miami around the clock, even now, even in the night hours- This it was and nothing more.

But I put my foot down on the gas pedal anyway. I moved up, in and out of traffic. I got within three cars of the Corniche and its besieged driver. Traffic stopped. I looked ahead at the truck. It was running straight up Biscayne, moving into a series of traffic lights. I would lose him if I got too far behind. And I suddenly wanted very badly not to lose him.

I waited for a gap in traffic and quickly nosed out into the oncoming lane. I was around the Corniche and then speeding up, closing on the truck. Trying not to move too fast, not to be conspicuous, but slowly closing the space between us. He was three traffic lights ahead, then two.

Then his light turned red and before I could gloat and catch up, mine did, too. I stopped. I realized with some surprise that I was chewing on my lip. I was tense; me, Dexter the Ice Cube. I was feeling human anxiety, desperation, actual emotional distress. I wanted to catch up to this truck and see for myself, oh how I wanted to put my hand on the truck, open the door to the cabin, look inside-

And then what? Arrest him single-handed? Take him by the hand to dear Detective LaGuerta? See what I caught? Can I keep him? It was just as likely that he would keep me. He was in full hunting mode, and I was merely tagging along behind like an unwanted little brother. And why was I tagging along? Did I just want to prove to myself that it was him, the him, that he was out here prowling and I was not crazy? And if I was not crazy-how had I known? What was going on in my brain? Perhaps crazy would be a happier solution after all.

An old man shuffled in front of my car, crossing the street with incredibly slow and painful steps. For a moment I watched him, marveling at what life must be like when you moved that slow, and then I glanced ahead at the refrigerator truck.

His light had turned green. Mine had not.

The truck accelerated quickly, moving north at the upper end of the speed limit, taillights growing smaller as I watched, waiting for my light to change.

Which it refused to do. And so grinding my teeth-steady, Dex!-I ran the light, narrowly missing the old man. He didn't look up or break step.

The speed limit on this stretch of Biscayne Boulevard was thirty-five. In Miami that means if you go under fifty they will run you off the road. I pushed up to sixty-five, moving through the sparse traffic, desperate now to close the distance. The lights of the truck winked out as he went around a curve-or had he turned? I moved up to seventy-five and roared past the turn for the 79th Street Causeway, around the bend by the Publix Market, and into the straightaway, searching frantically for the truck.

And saw it. There-ahead of me-

Moving toward me.

The bastard had doubled back. Did he feel me on his tail? Smell my exhaust drifting up on him? No matter-it was him, the same truck, no question, and as I raced past him he turned out onto the causeway.

I squealed into a mall parking lot and slowed, turning the car and accelerating back out onto Biscayne Boulevard, southbound now. Less than a block and I turned onto the causeway, too. Far, far in front, nearly to the first bridge, I saw the small red lights, winking, mocking me. My foot crashed down on the gas pedal and I charged ahead.

He was on the up-slope of the bridge now, picking up speed, keeping the distance steady between us. Which meant he must know, must realize somebody was following. I pushed my car a little harder; I got closer, little by little, a few lengths closer.

And then he was gone, over the hump at the top of the bridge and down the far side, heading much too fast into North Bay Village. It was a heavily patrolled area. If he went too fast he would be seen and pulled over. And then-

I was up the bridge and onto the hump now and below me-

Nothing.

Empty road.

I slowed, looking in all directions from the vantage point at the top of the bridge. A car moved toward me-not the truck, just a Mercury Marquis with one smashed fender. I started down the far side of the bridge.

At the bottom of the bridge North Bay Village split off the causeway into two residential areas. Behind a gas station on the left a row of condos and apartments made a slow circle. To the right were houses; small but expensive. Nothing moved on either side. There were no lights showing, no sign of anything, neither traffic nor life.

Slowly I moved through the village. Empty. He was gone. On an island with only one through street, he had lost me. But how?

I circled back, pulled off onto the shoulder of the road and closed my eyes. I don't know why; perhaps I hoped I might see something again. But I didn't. Just darkness, and little bright lights dancing on the inside of my eyelids. I was tired. I felt stupid. Yes, me; ditzy Dexter, trying to be Boy Wonder, using my great psychic powers to track down the evil genius. Pursuing him in my supercharged crime-fighting vehicle. And in all likelihood he was simply a stoked-up delivery boy playing macho head games with the only other driver on the road that night. A Miami thing that happened every day to every driver in our fair city. Chase me, you can't catch me. Then the uplifted finger, the waved gun, ho-hum and back to work.

Just a refrigerated truck, nothing more, now speeding away across Miami Beach with the heavy metal station ripping from the radio speaker. And not my killer, not some mysterious bond pulling me out of bed and across the city in the dead of night. Because that was just too silly for words, and far too silly for level-headed empty-hearted Dexter.

I let my head drop onto the steering wheel. How wonderful to have such an authentic human experience. Now I knew what it was like to feel like a total idiot. I could hear the bell on the drawbridge in the near distance, clanging its warning that the bridge was about to go up. Ding ding ding. The alarm bell on my expired intellect. I yawned. Time to go home, go back to bed.

Behind me an engine started. I glanced back.

From behind the gas station at the foot of the bridge he came out fast in a tight circle. He passed me fishtailing and still accelerating and through the blur of motion in the driver's window a shape spun at me, wild and hard. I ducked. Something thumped into the side of my car, leaving behind it the sound of an expensive dent. I waited for a moment, just to be safe. Then I raised my head and looked. The truck was speeding away, crashing the wooden barrier at the drawbridge and powering through, leaping across the bridge as it started to raise up, and making it easily to the other side as the bridge keeper leaned out and yelled. Then the truck was gone, down the far side of the bridge and back into Miami, far away on the other side of the widening gap as the bridge went up. Gone, hopelessly gone, gone as if he had never been. And I would never know if it had been my killer or just another normal Miami jerk.

I got out of my car to look at the dent. It was a big one. I looked around to see what he had thrown.

It had rolled ten or fifteen feet away and wobbled out into the middle of the street. Even from this distance there was no mistaking it, but just to make sure I was absolutely without any doubt, the headlights from an oncoming car lit it up. The car swerved and smashed into a hedge and over the sound of its now-constant horn I could hear the driver screaming. I walked over to the thing to be sure.

Yes indeed. That's what it was.

A woman's head.

I bent to look. It was a very clean cut, very nice work. There was almost no blood around the lip of the wound.