At the very moment I spotted him in the mirror, he tried to plunge the blade into my spine.

A jolt of terror went through me, an electric panic that gave me almost supernatural speed. I leapt to my left, turning sideways. The blade lanced past my midsection, so close I felt its motion through the fleece. My years of karate training kicked in. I reacted without thinking, smacking his elbow with my left palm to push the knife hand away.

But I was moving so fast, in so much fear, I stumbled, tripped over my own feet, and staggered back deeper into the bathroom.

That saved my life. Because the man with the knife was well-trained. He knew how to fight. He was already slashing backward at my face. If I hadn't stumbled away from him, he'd have cut my throat right there.

I let out a grunt, bending away from the blade. I still didn't have my feet under me, and the movement sent me even farther off balance. I fell, tumbling down to the floor.

It was the end of me. I was sure of it.

You have to understand: a trained man with a knife is as deadly as anything, even more dangerous in some ways than a man with a gun. You might grab a gun. You might wrestle it away. But you can't get hold of a knife without getting cut. And if the knife-man knows what he's doing, he can carve you up with a blade just as fast as a bullet.

And this guy knew what he was doing, all right. All the karate training in the world wasn't going to save me if I didn't act fast and act smart. If I fell and he came down on top of me, I'd be dead in seconds.

I knew it even as I was falling. The panic raced through my belly. The thoughts raced through my head: I have to do something.

I hit the tiled floor and kept rolling, fast, away from the oncoming killer. I rolled and leapt up, gaining my feet in the back of the bathroom, pressed up against the far wall, the urinals on either side of me.

Before I could even think, he was there, he was on me, driving the knife toward my gut, the black blade glinting in the light.