I looked around to make sure no one had edged close enough to overhear. Not to worry. There wasn’t a person in this trendiest of hangouts who wasn’t more interested in him-or herself than anyone else in the room.

“If you want to do something short of slashing faces and detonating nuclear bombs, I’m with you. But I’m not up for hurting anyone.”

She turned and found something interesting to look at on one of the three big-screen TVs.

“What’s it going to be, Angel?”

The quickest way to walk home from Angel’s neighborhood was across the Common and through the Public Garden. The second I was out of her range, I called Harvey.

“I saw Angel,” I told him when he picked up. “I just left her.”

“You just left? It’s almost eight o’clock.”

“She insisted that we go to dinner.”

“What did you learn?”

“I learned why your top swapper list excludes the senior women.”

I explained Angel’s organization and the concept of pool girls to him, occasionally checking around to see if anyone nearby was listening to me. My side of the conversation would have made for some bizarre eavesdropping. Harvey liked the explanation because it made perfect sense. I was more interested in how to fill the gap in our investigation.

“We definitely have to get to the Web master,” I said. “If Felix can’t get in through the back door, then I need to get to him through Angel.”

“How would you do that?”

“I tried to get her to talk about him, but she wouldn’t bite. She gets how important he is. We’ve set up another meeting tomorrow to talk about the frequent fucker program.”

“Another workout?”

“No. She wants me to come up to her house in New Hampshire.”

As I passed the tennis courts, I was delighted to hear that my favorite busker was out, even at this hour. The accordion player was on his customary stoop under a big oak, spinning sweet songs in minor keys and making a crosswalk in the middle of a Boston park feel like an outdoor café in Paris. He smiled and nodded as I dug out a dollar and dropped it in his case. I sat on a nearby bench to listen while I finished my conversation with Harvey.

“There’s something else,” I said. “Angel has no fear at all of getting caught and going to jail. None. She acts as if she has some kind of get-out-of-jail-for-free card.”

“What could that be?”

“I don’t know. Maybe a rabbi. Someone to watch out for her. From the sound of it, it would have to be someone pretty powerful. She calls it her nuclear bomb. Whatever it is, it gives me some concern.”

“How so?”

“Let’s say we build a case against Angel. Will she be able to pull out this hole card and use it to beat us? Would it be something that keeps the airline from firing her?”

“It is not our job to guarantee her termination. Only to give the client what he has asked for.” Harvey was veering into lecture territory, which meant it was time to change the subject.

“I finally got Monica’s address. I’m heading over to her apartment as soon as I change. I want to try to get over there before it gets too late.”

“Do you think she will be there?”

“Not a chance. But I would feel pretty stupid if she’s there watching Oprah and not answering the phone and I never even went by and knocked on her door.”

The accordion player finished “ La Vie En Rose” and put down his instrument to take a break.

“Alex, are you there?”

“I’m here.” I had been thinking abut Angel’s threat to have someone slashed. I was thinking mostly about how perfectly capable she was of doing it.

“There’s one more thing, Harvey. Have you had any more conversation with the retired detective in Omaha?”

“No. Should I?”

“I think so. We need to look more closely at this Robin Sevitch murder.”

I CALLED FELIX FROM THE CAR ON THE WAY TO Monica’s. With the reintroduction of Felix to my life, I’d had to rearrange the turbo-dialing buttons on my cell phone. Felix’s number replaced the Majestic Airlines reservations line. The last electronic vestige of my association with my old airline got bumped down to regular speed dial.

“Hey, Miss Shanahan.”

“Hi, Felix. I’m just checking in. How are things?”

“I had an emergency at the airport. The bag belt broke down, and I had to go in and fix it.”

“We agreed that your airport job takes priority.”

“I know, but it shouldn’t be so much trouble, you know? The problem is, it’s such a lame program. It breaks down all the time. I’m working with the manufacturer to get some of the bugs out. It wasn’t designed to handle variable workload, which is really kind of useless when you think about the fact that it was built for an airline, an operation with variable scheduleand variable workload. It needs to be run against dynamic-”

“Felix.”

“Yes, ma’am?”

“Have you had any progress on the case?”

“I’ve been looking around Mr. Margolies’s hard drive, and I found a couple of other bits and pieces related to that video. The one with-well, you know. Ohmygosh, Miss Shanahan. That was really something. Do you know that lady?”

I had to pause for a smile. Felix’s outsized competence made him seem so mature, it was hard to remember how young he was. He had hormones that raged like any kid barely out of high school.

“She had her clothes on when I met her.”

The red taillights were lined up for blocks down Commonwealth. “Hold on a second, Felix.” I put the phone down and cut across two lanes so I could turn, take Storrow, and miss the lights. That put me in a long line of left-turners but gave me plenty of time to listen.

“Go ahead, Felix. Did the bits and pieces tell you anything?”

“Just that he uses a lot of layers and misdirection. But I already knew that.”

“You said ‘he.’ You don’t think Monica could have sent it?”

“Well, I’m not saying she couldn’t have. I mean, she could be a hacker, too, that lady in the video. The hacker could be a she, is what I’m saying. Just because she looks the way she looks doesn’t mean…that would be sexist, right? To think that way would-”

“Felix.”

“Whoever he is, he’s the same person who set up that other site you sent me. The one using the reverse proxy server.”

“Wait a second. The guy who set up the scheduling site for Angel?”

“Him, yeah. I call him Web Boy because he’s like a super-hacker. Only he’s a dark force.”

“How do you know it’s the same person?”

“Because he left a fingerprint.”

“A fingerprint?”

“In the code. Hackers are like that. They like to sign their work, you know? For other hackers who know what to look for.”

“I’ll be damned. That means Angel’s Web master is in on this blackmail scheme.”

“Same fingerprints on both the Web site and Mr. Margolies’s stuff, basically. Only I don’t think he was as careful with the video program as he was with the site. If we could find the e-mails that came with it, I could probably tell you who it is.”

“Or”-this was starting to feel significant-“if we could find Monica, then we might be able to get to the Web guy through her. What did you call him?”

“Web Boy, the Dark Hacker.”

As distinct from Felix, the Boy Genius. I liked that. “Maybe Web Boy is the one who catalogues all of Monica’s videos.” Which meant both of them would have something to hide from Angel.

“He could be.”

My light had been green for a while, but the traffic wasn’t moving. When it finally loosened up, it was just enough to get me all the way up to the front of the line, where I was hitting the gas as the yellow light turned red again. I slammed on the brakes and sat back to wait through another cycle.

“Anything else, Felix?”

“Not so far.”

“Good job. Keep working on finding Web Boy. I’ll work on finding Monica.”