I eddied out at the bottom of the run, below what paddlers call a “hole,” where the steepness of the drop causes the flow of the water to recirculate, creating a vortex capable of sucking a boat under. It was the only part of the river about which Arch had expressed any real concern. He’d urged us to paddle hard throughout and throw our weight forward at the bottom. Even though I was doing as I’d been told, I’d felt the hole sucking me down for a jarring, petrifying moment, grasping at the stern of the kayak before the current caught the hull and spit me out into flat water.

I turned and saw Vanessa’s boat, still upended, bobbing in the shallows on the far side of the eddy. Arch was already ashore and running back upriver.

A lone paddler in a narrow kayak floated up the crest of the great wave crashing against the canyon wall and hurtled into the chute with practiced grace. He was a bearded man, maybe about forty, wearing a fiberglass helmet. He came up alongside the bank beneath me.

“Our friend swam,” Arch shouted. “Did you see her?”

The man shook his head.

Arch took off running. The bearded man and I got out of our boats. He gathered a throw rope and a first-aid kit. We came up over the rocks and spotted Vanessa, floating against the far wall of the canyon, in the eddy. The cliff around her was vertical, featureless, far too slick for her to climb out. Her face was frighteningly pale.

Arch mounted a large boulder jutting out over the current. I thought he meant to hurl a rope to her; instead, he leapt into the air and disappeared into the river. A moment later, he surfaced and swam toward Vanessa. He wrapped his arms around her and spoke close to her ear. Vanessa nodded, her own face mirroring Arch’s fixed determination.

Arch pushed off the wall, holding Vanessa from behind. They hit the chute and disappeared. Their heads popped up just as they descended into the current, hurtling toward the hole below. Just before he went under, Arch pushed Vanessa forward, flinging her past the danger and out toward the gentle water as he vanished beneath the roiling foam.

The bearded man tossed his throw rope to Vanessa. I stood at the edge of the bank, searching for Arch below the surface of all of that noisy, bubbling water. The seconds stretched on. Counting aloud, I realized with mounting dread that he’d been down for close to a minute. For an instant, I tried to fathom the unthinkable. And then he popped up, gasping for air, some sixty feet beyond where he’d gone under.

“Hot damn. He swam right down into it, below the current,” the man said. “Down’s the only way out. Smart kid. That hole’s a killer.”