THERE'S MY BOY, Paul thought as Scott Thayer threw open the side door of the garage. Hey there, Scotty.

Dressed all in black and crouched in the shadows along the ivy-covered wall beside Scott's parked motorcycle, Paul knew he wouldn't be seen. Besides, it was raining like hell.

Paul hefted the golf club as Scott came across the driveway and entered the dark street. Time to show this son of a bitch the error of his ways.

Scott was ten feet away. Five.

Then suddenly, inexplicably, horribly, there was music blaring from somewhere. From him! From Paul's jacket pocket! His cell phone was going off!

No! Paul thought, reaching down to silence the stupid "Tainted Love" ring tone. Why the hell hadn't he left his cell in the car?

He was fumbling to turn it off with his free hand when Scott Thayer crashed into him at a run. Paul's breath left him as he was knocked backward onto the muddy ground.

He looked up, meeting Scott's wide eyes.

"You!" Scott said in shock. The golf club disappeared out of Paul's hand as Scott kick-smashed his motorcycle boot into Paul's fingers. Then Scott lifted Paul off his feet and threw him into the air. Paul cried out as his back struck something painfully hard. It was the Ducati. He and the bike went over in a pitiful heap.

"If I didn't know any better, I'd think you were planning on doing me some harm tonight, Mr. Stillwell," Scott said, not even breathing heavily. He lifted the fallen club as he slowly approached.

"Something like this could really hurt somebody," Scott said, waving the 3 iron at him like a chiding finger. "Here, let me show you."

I STOOD THERE, FROZEN, my nose millimeters from the rain-streaked glass as I looked out at the private street in front of the garage.

I couldn't believe what I was seeing. This isn't happening, I thought. It can't be happening.

Paul was here?

And he and Scott were fighting in the street! Really going at each other.

I'd gone to the window when I heard the crash of the motorcycle. Then I found myself immobile, unable to do anything but stand and stare at the unbelievable scene.

Of course Paul was here, I thought, reeling. What an idiot I'd been! Scott and I hadn't been discreet. We'd sent e-mails back and forth. I'd actually put Scott's number in my cell phone. Paul had simply started keeping tabs.

Guilt rattled through me. And fear.

What had I been thinking?

For weeks I'd tortured myself, imagining Paul with his blonde lover. Night after night, I'd envisioned them making love in their St. Regis suite. I was wallowing in the pain that only a spouse who realizes they're being cheated on feels. Pathetic.

But imagining was one thing.

Doing the same thing as revenge was another.

I'd just had a quickie for Christ's sake!

I watched, helpless, as Paul and Scott crashed into each other. Then the fight moved out of my line of sight, blocked by the vine-covered wall across the street. The two of them became just shadows. Violent ones that grappled and walloped and kicked at each other. What was happening now?

I couldn't think of what to do. Call out? Try to stop them?

And I was only looking at the preamble. It would be even worse when the fight was over and Paul came inside. When I had to face him.

I didn't know how I was going to do that.

Suddenly, there was a tremendous crack, like a well-hit baseball, and I didn't have to think about it anymore.

Both shadows stopped moving.

Then one dropped. He actually bounced off the ground before he lay completely still.

Who was hurt? Who was down? I wondered with a kind of dumbstruck curiosity. Then the scariest question of all occurred to me. One that took my breath away as it nicked through my heart like a cold razor.

Who did I want it to be?

FOR A HEART-PUNISHING MINUTE, everything was dead still. The shadow figures outside. My breathing. Even the rain appeared to have stopped. The silence was so absolute it seemed to ring.

Then from out of it came a far-off thump. Then another thump. Thump, thump, thump. I thought it might be the sound of my heart amplified by terror until a silvery glow cut through the darkness.

The unmistakable throbbing assault of cranked-up rap music reached my eardrums as a tricked-out Acura pulled onto the street and then into a driveway at the far end of the block.

For the briefest moment, powerful xenon headlights lit the opposite side of the street, revealing the unforgettable scene in its startling entirety.

It only took a millisecond, but that was more than enough time for the image to be burned forever into my memory.

The standing shadow was definitely Paul. He was breathing heavily, holding Scott's motorcycle helmet in his hand like a club.

Scott lay at his feet, a golf club near his hand, a black halo of blood beneath his head.

This is what happens when you cheat, a voice whispered in my ear.

This is what you get.

Then, at that moment, I did the most constructive thing I could think of. I dropped away from the window and hid my face in my hands.

Scott was down, not moving.

Because of me.

I was still in full-body lockdown, fumbling with these new, numbing realities, when another thought occurred to me.

Was Paul crazy enough to come after me, too?

Overcome with the need to see where Paul was now, I went back to the window.

What the hell?

Parked directly behind Scott's fallen motorcycle, in the dome of light, was Paul's car. I watched in horror as Paul tossed Scott onto the backseat. It seemed like Scott's head banged against the door frame, and I heard him groan.

What did Paul think he was doing?

Finally, I rushed down the stairs of the apartment. I couldn't let this continue. I went through CPR procedure in my head. Mouth-to-mouth. I was almost at the door when I suddenly realized I didn't have any clothes on. I hurried back upstairs.

I had my T-shirt on and was fumbling with my jeans when I heard the thunk of a car door closing, and then the sound of tires spinning.

I rushed to the window again.

I looked out just in time to see Paul's car speeding away.

My chest burning, my head spinning, I had one more question for Paul as I watched the car's red running lights disappear into the darkness.

Where the hell are you going with Scott, Paul?

IT TOOK ME A FULL TWO MINUTES to realize what must have happened. Two mind-and-body-numbing minutes of leaning my head against the cold, rain-streaked glass. I smiled when the sweet logic of it suddenly struck me. For the first time that night, my heart slowed slightly and approached a semi-human rate.

Paul must have taken Scott to the hospital.

Of course he had. Paul had come to his senses. Sure, he'd lost it for a few minutes. Who wouldn't, catching up with the man who was sleeping with his wife? But after Scott had gone down, Paul finally snapped out of it.

They had to be pulling up to the emergency room of the closest hospital right now.

I called a taxi and arrived back home in Yonkers an excruciating forty minutes later. I threw open the door and stood there, staring at the microwave clock in the silent house.

Where was Paul? Shouldn't he be back by now? What was happening?

I decided Paul had taken Scott to Lawrence Hospital, about ten minutes away from Scott's apartment. But now over an hour had passed. There was no word. Had something even more terrible happened? Maybe Paul had been arrested.

I checked the answering machine upstairs, but other than my gynecologist's dispatch on my failing health, it was empty. After another five minutes, spent staring at the empty street, I seriously considered giving Paul a call on his cell to see what was going on. The problem was, I didn't know exactly how to phrase things.