IT DIDN'T TAKE long for Tony Nicholson to start talking a blue streak about the club and the blackmail scheme after that. I'd seen it so many times before, the way suspects will start competing with each other once they sense the ground is shifting. To hear him tell it, Mara Kelly had set up the entire back end: Asian underground banking, public key cryptography – everything they needed to stay out of reach for as long as they had.

"Why do you think they came after her too?" he kept asking us. "Don't be fooled by the pretty face. That bitch isn't nearly as stupid as she appears."

I guess you could say those two were no longer an item. Now things might get interesting.

Nicholson had been sitting on the same rickety folding chair for hours, with his injured leg stuck out to the side in an immobilizer. From the twisted look on his face, he was coming due for a pain pill.

"Okay," I said. "That's a start, Tony. Now let's talk about the real reason we're here."

I took out a file and started laying photos on the table. "Timothy O'Neill, Katherine Tennancour, Renata Cruz, Caroline Cross."

There was a moment of genuine surprise on his face – but just a moment. Nicholson was cool under fire. "What about them?"

"They all worked for you."

"It's possible," he said. "A lot of people work for me."

"It wasn't a question." I pointed at Caroline's picture. "She was found mutilated beyond recognition. Did you catch that on camera too, Nicholson?"

"I seriously don't know what you're talking about. I have no idea what you're getting at. Try making sense when you bother to open your mouth."

"How did she die?"

Something seemed to click suddenly, like a spark in Nicholson's eyes. He looked down at the picture and then back up at me.

"You said Caroline Cross? That's your name, isn't it?" When I didn't answer, his mouth spread into a grin. "Excuse me, Detective, but I think maybe you're in over your head."

"I got up very fast. If the table hadn't been bolted to the floor, I might have pinned Nicholson to the far wall with it.

But Sampson got to him first. He shot around the table and pulled the chair right out from under him. Nicholson flopped onto the floor like a caught fish.

He started to scream. "My leg! My goddamn leg! You bastards! I'll sue you both!"

Sampson didn't seem to hear. "You know Virginia 's a death penalty state, right?"

"What is this, Abu fucking Ghraib? Get the hell away from me!" Nicholson gritted his teeth and pounded the floor. "I didn't kill anyone!"

"But you know who did," I shouted back.

"If I had anything to trade, don't you think I'd use it? Help me up, you stupid assholes! Help me up, here. Hey! Hey!"

We walked out instead. And while we were at it, we took the chairs with us.

FOUR HOURS LATER, in the name of "coming clean" and telling us what he knew, and most of all, getting the best deal he possibly could, Nicholson offered up access to a safe-deposit box in DC. He said it contained evidence that could help us. I had doubts, but decided to take my progress with him incrementally.

It took some scrambling, but by the next morning Sampson and I were outside the Exeter Bank on Connecticut with fully executed paperwork, a key from Nicholson's desk, and two empty briefcases in case there really was evidence to retrieve.

This place was no ordinary savings and loan, starting with the fact that we had to be buzzed in from the street. The lobby had a do-not-touch kind of feel to it – not a pamphlet or a deposit slip in sight.

From the reception desk, we were directed up to a row of glass-walled offices on the mezzanine. A woman inside one of them put down her phone and turned to look at us as we started up the stairs.

Sampson smiled and waved at her. "Feels like a damn James Bond movie," he said through his teeth. "Come in, Dr. Cross. We've been expecting you."

The branch manager, Christine Currie, was indeed expecting us. Her brief smile and handshake were about as warm as yesterday's oatmeal.

"This is all a bit irregular for us," she said. Her accent was stuffy and British, and more upper-crust than Nicholson's. "I do hope it can be done quietly? Can it be, Detectives?"

"Of course," I told her. I think we both wanted the same thing – for Sampson and me to be back on the street as soon as possible.

Once Ms. Currie had satisfied herself with our paperwork and compared Nicholson's signature in half a dozen places, she led us out to an elevator at the back of the mezzanine. We got on and started down, a very rapid descent.

"You guys do free checking?" Sampson asked. I just stared straight ahead, didn't say a word. Stuffy environments sometimes set John off. Stuffy people too. But most of all, bad people, criminals, and anybody who aids and abets.

We came out into a small anteroom. There was an armed guard by the only other door, and a suit-and-tie employee at an oversize desk. Ms. Currie logged us in herself, then took us straight through to the safe-deposit room.

Nicholson's box, number 1665, was one of the larger ones at the back.

After we'd both keyed the flap door, Ms. Currie pulled out a long rectangular drawer, then carried it to one of the viewing rooms off an adjacent hallway.

"I'll just be outside, whenever you're ready," she said in a way that sounded a lot like Don't take too long with this.

We didn't. Inside the box, we found three dozen disks, each one in its own plastic sleeve and dated by hand in black marker. There were also two leather binders filled with handwritten pages of notes, lists, addresses, and ledgers.

A few minutes later, we left with all of it in our briefcases.

"God bless Tony Nicholson," I said to the unflappable Ms. Currie.

FOR THE REST of the afternoon, Sampson and I holed up in my office with a pair of laptops. We stayed busy watching and cataloging the extracurricular sex lives of the rich and mostly famous. It was surprisingly repetitive stuff, especially given everything that Tony Nicholson was set up to provide at the club.

The roster of power players, on the other hand, was one big holy shit after another. At least half the faces were recognizable, the kind of people you'd see at a presidential inauguration. In the front row.

The clients weren't just men either. Women were outnumbered about twenty to one, but they were there, including a former US ambassador to the United Nations.

I had to keep reminding myself that every one of these people was – at least technically – a murder suspect.

We set up a log, using the date stamps embedded on each recording. For every clip, we wrote down the name of the clients we recognized and flagged the ones we didn't. I also made a note of where each "scene" took place at the club.

My primary interest was the apartment over the carriage barn, which I'd come to think of as a kind of ground zero for this whole nasty murder puzzle.

And that's where we started to pick up some legitimate momentum. Right around the time I thought my eyes were going to burn out of my head, I started to notice an interesting pattern in the tapes.

"John, let me see what you've got so far. I want to check something."

All of our notes were handwritten at this point, so I laid the pages out side by side and started scanning.

"Here… here… here…"

Every time I saw someone had used the apartment, I circled the date in red pen, ticking off entries as I went. Then I went back over everything I'd circled.

"See this? They were using the studio in the back pretty regularly for a while, and then, about six months ago, it just stops cold. No more parties back there."