I was looking from above at the bare branches of an enormous tree—a bird'seye view. It was a goddamn pecan tree at the bottom of the lake.

I heard an omnipresent plink, plink: Lopez, getting my attention by knocking the butt of his knife against his air tank. I could barely see him, two feet away from me, until I shone the flashlight on him. He was waving one palm horizontally over the knife—the sign to level out.

I was descending too fast, getting too close to the tree. I kicked up, added a little air to the BC, and my fin brushed against a branch. An ancient, open pecan pod snapped away from the top of the tree and went spinning into the void, its petals like a black claw.

Another two seconds and I would've been ensnared in branches.

I flashed my light around and momentarily lost the rope, and Lopez. Then, just as suddenly, there he was. I could see the danger— how easy it would be to get disoriented, tangled, panicked.

We floated, suspended above the tree, shining our lights on each other. I felt colder than I'd ever felt. My whole body was tight, like I'd been shoehorned into a much smaller man's wet suit.

Lopez signed, Okay?

I should've made the soso gesture, but I responded Okay.

Lopez tapped his computer. I checked mine. My air supply read 2,700 psi. Depth: ninetyeight feet. Lopez pointed to the rope, then down to the tree, then used more gestures to indicate that since the rope had gone straight through the branches, we'd have to navigate around the circumference of the tree and underneath. Was I okay with that? I made the Okay sign.

He tapped his watch, held up ten fingers. Ten minutes. The clock had started running.

We turned horizontal, angled ourselves down, then carefully descended around the periphery of the pecan tree.

It must've been a monstrous specimen when alive, and down here in the murk it seemed even bigger. We tried to keep a safe distance, but the tree kept surprising us.

We kept getting brushed and snagged, clawed at, almost impaled on branches that were worn to silty pikes from the decades underwater.

Then, at last, we were below the lowest boughs, shining our lights on a trunk so large our hands might just have met had we tried to hug its diameter.

Lopez plinked to get my attention again, gestured with his flashlight. He was warning me not to get too close to the bottom. It wasn't really solid below me—just a fuzzy layer of silt, lumpy and pitch black, like the remains at the bottom of a barbecue pit. Our line from the surface went straight down into the stuff, the anchor completely submerged.

Lopez gestured for me to come over and stay by the rope. He produced a second line from his supply bag—the tender line. He made a loose shepherd's knot, and slipped it around my wrist. He checked his computer, apparently calculating our GPS, then pointed off in one direction, pointed to himself.

I nodded.

Lopez measured out two yards of line the way they do in fabric stores—running the line from his nose to extended thumb. He handed me the slack. Six feet seemed a ridiculously small distance to start with, given how little time we had, but then Lopez moved away, and within a few feet he was gone.

There was no logic to it, what you could see and what you couldn't. In one direction, through a clearer patch of water, I could almost make out the trunk of the next tree in the row, but I couldn't see Lopez six feet away. If I shone my flashlight directly on him, I could just barely make out a smudge of black.

He gave me two quick tugs on the rope. I fed him another six feet of line, and then he was gone completely. I was alone.

I shone my light up through the branches of the ancient pecan. It must've been frozen in winter, fiftyplus years ago, but it looked

like it might've been submerged yesterday. There were still hardened knobs of pecans clinging to a few branches, more delicate black claws of open pods—things you would not think could withstand the flooding of an entire valley. The texture of the bark was still discernible. I wondered if the McBrides had picnicked here once, looked up at the sun through the branches, been grateful for the shade back on a Texas summer day before they'd had airconditioning, when Austin had still been a small town a day's wagon ride away.

I reminded myself, a little dreamily, that I'd come down here to do a job. I checked my console—one hundred two feet below. The timer read 12:04 minutes, total dive time.

My breathing had almost slowed to normal. I was relaxed. I started smiling for no particular reason, staring up into the branches of the tree.

Then I was brought back to reality by one sharp tug on the tender line. It meant more than just stop. We hadn't discussed it, but I was afraid that kind of tug must mean, 1

found something.

I waited. The cold enveloped me.

I calculated that Lopez was fifteen feet away now, but I couldn't see anything except the faintest bleached spot in the dark, perhaps his flashlight.

He gave three tugs, the signal that I was to come to him.

Not quite sure what to do with the line, I tied my end to the lead line, then, slowly, kicked my way into the gloom, my hand cupped loosely around the tender as I followed it out. Ahead was a tall streak of darkness—the trunk of the next tree. There was a smaller shape, too, with a tiny shimmer above it—Lopez and his bubble stream.

I got close enough to see him. He was floating right in front of the tree trunk as if examining it, his back to me. I kept my flashlight beam on him.

The beam of my light must've caught his attention, because he turned.

And that is when I realized I was going to die one hundred feet underwater.

Lopez's eyes were wide inside his mask, hardly human. One orangegloved hand held his dive knife, the point level to my nose, the thin blade toward me, serrated edge out.

Just beyond him, in front of the tree's trunk, was the thing.

It wore a wet suit, its limbs floating loosely in the current. A cord was wrapped around its legs, tying it to the same anchor that had sunk it into the muck. There was a severed regulator rope floating like a dead vein, and a metal dive knife impaled to the hilt just under the thing's sternum. The face had lost all definition, and the hair was a billowy, colourless mass until the beam of my flashlight touched it?

then it flared orangered. And the eyes turned to glass. The mouth opened, and I was sure those white hands reached out to me.

I screamed an explosion of bubbles, kicked, flailed away, and suddenly found that I wasn't moving. I couldn't see the dead face anymore, just endless crosses and hooks of black wood, and something was holding me fast from behind. I lost my mouthpiece, clamped my teeth, panicking, ready to inhale lake water, then somehow managed to find the regulator again and breathe.

My flashlight beam crossed with Lopez's. He emerged not three feet away, still holding the knife pointed toward me, a look in his eyes that I could not mistake.

I kicked, swiped at him with my fins, heard a crack that came from everywhere, and then I kicked again and found I was free. The world exploded in an ink cloud. My flashlight slipped out of my hand.

There was no sight, no sound except my own exhale bubbles and the steady suck of air into my lungs from the regulator, dry and steady.

I tried to breathe normally. I'd stirred up the bottom. What had Lopez said about that?

Swim east. Could I trust him? I'd seen the shore. It was east.

I groped along the top of my tank until I found the pressure gauge that led to my computer console. I brought it in front of my face, pressed buttons on the side until I found the one that made the console illuminate.

Suddenly I wasn't alone. I had faint, green dials to keep me company. I turned until the compass said I was pointing east. Then I started kicking slowly in that direction, still completely blind.

I heard the plinkplinkplink of Lopez's knife on his tank. Was he in front of me? Or behind? The plinking sounded more urgent than it had before. I slid my own knife out of the sheath on my leg, but my hand was so cold even through the glove that I couldn't feel the handle, much less see it. I let it go in the darkness.

I kept kicking—three cycles of leftright. Twelve cycles. I checked the console and found I had about nineteen minutes of air left. I'd been underwater for only sixteen.

I began to see again—the gentle slope of the lake bottom under me. Rocks the size of sofas rose out of the silt, and moving among them, catfish as big as I was. The black was turning to green. I could see the lower spectrum of colours.

I checked my depth and found that I'd risen to sixtytwo feet. I stopped, and had no idea where I was. I was supposed to do something— Go up. Go up slowly. I followed the rocky slope.

At thirty feet I stopped, sat on a furry, silted ledge that had probably once looked over the river valley. It now offered a view of a dark green void. I forced myself to time ten more minutes, which according to the computer left me fourteen minutes of air. I knew the math wasn't right, somehow. Then I remembered that I was using less compressed air as I ascended.

Another ten feet of gradual ascent and I could see the surface—a flashing sheet of silver and yellow. The fish were now clear. I loved every speckle on every trout, every whisker on every catfish. If I'd had a package of hot dogs, those fish would've eaten like kings.

I forced myself to wait ten more minutes to expend the extra nitrogen. I stared into the green, tried to remain calm, tried to sort out the reality from the fantasy. What had happened down there?

Finally, I kicked up and broke the surface in the late afternoon light. I almost sunk below the surface again, then inflated my BC. I ripped the mask off my face, spit out the regulator. The air burned from the summer heat. It was charged with the smell of approaching storm and cedars. I promised myself I would never complain about cedars again, no matter how bad the pollen fever season got.

The Flagship of Fun was floating not thirty yards away—so impossibly close it made me angry, given the odyssey I'd just completed.

There was no place I wanted to go less, just then, than the Flagship of Fun. But I could hear the voices clearly over the water— Clyde, Lopez, and most frantic of all, Maia.

I yelled, "Hey!" with more anger than I knew I had, letting out twentytwo minutes of terror in a single word.

Lopez and Maia rushed to my side of the boat.

Maia spotted me and her whole body seemed to sag under the weight of an extra G

force. "Oh God. Oh thank God."

Lopez yelled, "You son of a bitch!"

He'd stripped off his gear except for his mask, which was still stuck to his forehead—the sign of a diver in distress. I don't think, at that moment, Lopez cared what signals he sent.

His face was livid, but the look in his eyes was not what it had been at one hundred feet. It was not wild. He yelled: "You could've killed us both!"

I bit back comment, kicked over to the ladder on the boat.

Clyde was there, too, talking on a cell phone, giving the Lower Colorado River Authority our position. His expression could've been carved out of slate.

Lopez helped me aboard, Maia taking my other arm. I let them help me get my gear off.

Then I turned to Lopez just as he was starting to cuss me out and I slammed a right uppercut into his jaw.

His teeth clacked shut and his head did a little snap. He staggered back, looking momentarily stunned. That was all. I must've been even weaker than I felt.

Lopez's face hardened, got very calm. Then he charged me. He knocked me to the deck, began throwing sloppy punches into my ribs and face, kicking, kneeing. Clyde was above Lopez, trying to pull him off, either because he wanted to break it up or because he wanted his own shot at one or both of us.