We strolled. Ambled. There were lights above the stores, and I saw a woman's shadow on a beige curtain and, below the window, walked through the strong, acrid smell of home permanent. Metallica pounded from a radio down an alley.

"The problem with nights like these, where you've got apartments above the stores, is that people without air-conditioning sit in the windows, in the dark," LuEllen said. "If somebody sees us go in, I hope they don't notice that no lights come on inside."

It was just after ten o'clock. The time and temperature sign on the Longstreet State Bank said eighty-three degrees.

"There it is," LuEllen said. "The one with the brick."

The door was set at a shallow angle into the wall, surrounded by yellow brick. A brass plate was screwed onto the brick.

"Easy," LuEllen said. "Not too close to me. Look tired and impatient."

She walked up to the door, tugged at it, and used the key. The whole entry took five seconds. We pulled the door shut behind us and stopped to listen. We could hear the buzz of the lights from outside. The sound of an air conditioner in the building. Nothing else.

"When did Marvel say the janitor left?"

"Never misses a Cardinals game. He'd have been home an hour ago," LuEllen said. The hallway was lit by a single dim light. LuEllen led the way past a bank of elevators and into a stairwell, picked out the steps with a miniature flashlight, and led the way up one floor. At the landing she opened the door a crack, watching, waiting. Nothing. Then a sound. A voice. Muffled.

"Shit," she whispered. "There's somebody up here."

We listened some more.

"Two people. Man and a woman. They're. fooling around," she said.

"Where's Ballem's office?"

"Down to the right."

The sounds were coming from the left.

"So what do we do?" I asked.

"Let's go." She led the way into the hall, holding the door. When I was through, she eased it shut, and we walked carefully down to Ballem's office. The unseen woman laughed. LuEllen paused at Ballem's office door, her ear to the glass panel, waited five seconds, then unlocked it. Inside, she stopped me with a hand and disappeared into the dark. A moment later her light flicked on, and she said in a low voice, "All clear."

Ballem's personal office was at the end of a railway. LuEllen tried the door, found it locked, knelt on one knee to look at the lock, and grunted.

"Hold the light," she said. I took the flash, and she dug into her bag, coming up with a cloth roll tied with a string. Lockpicks. She unrolled the cloth, laid it on the floor, and, after a few seconds' study, selected a pick and a tensioner.

One miserable winter afternoon in St. Paul, with sleet beating against my north windows, we lounged in bed and LuEllen tried to teach me how to pick locks. I failed – I'm not patient enough – but I learned some of the technique and the names of the picks: the half-round and round feelers, the rakes and diamonds and double diamonds, the readers, extractors, mailboxes, flat levers and tensioners, circulars and points.

The lock on Ballem's door was a pin tumbler, in which a lock cylinder rotates to throw the bolt. The cylinder is prevented from rotating by five spring-loaded pins. The ragged edge of a key moves the pins up to a sheer line; when all the pins are moved up exactly the right distance past the sheer line, the cylinder can rotate.

LuEllen was locating each of the lock's five pins and gently moving them, one at a time, up to the sheer line. At the same time she kept pressure on the cylinder with a spring steel tensioning tool. It took time. I was sweating when she said, "Ah," then, "Wait." She made some more delicate movements; then, with a quick twist of her wrist, the door was open.

"Got too enthusiastic with that last pin, got it up too high," she said. She was panting from the stress; when you're picking a lock, you tend to hold your breath.

Ballem's office smelled of pipe tobacco and paper, with an undertone of bourbon. Most of the furniture was turn-of-the-century oak, practical, sturdy.

"Watch the light," LuEllen said quietly. A flashlight beam on a Venetian blind will bring the cops faster than an alarm. We didn't really need it anyway; the windows were at the same level as the streetlights, and enough illumination came through the shades that we could easily move around the office.

Two walls of the office were given to lawbooks, another to a series of English court prints taken from Punch. A narrow worktable ran along the fourth wall, with a row of file cabinets at one end. A half dozen plaques and framed certificates, testifying to service and study, hung on the wall above the table. The computer was on a walnut side table next to the desk. An IBM-AT, Marvel had said, and it was, with a low-tech printer on a stand behind it and a small three-hundred-baud modern. I breathed a sigh of relief. If it had been Macintosh or an Amiga, I'd have had to dump the high-capacity internal hard disk to smaller floppy disks, and that might have taken a while. As it was, I should be able to do the job in a few minutes.

I hooked up the Laplink, then handed the light to LuEllen, brought the machine up, stuck in a disk, and loaded a utility program of my own. A minute later I was looking through the hard disk, sending to my machine any text or financial files.

While I did that, LuEllen looked around the office, checking drawers. The file cabinets were locked, but she opened each in a matter of seconds and began going through the files.

"Not much here," she said. "It's all routine legal stuff. Real estate transfers, car accidents, workers' compensation forms. There's some city work, but it all looks like insurance and ordinances and printed budgets. Public stuff, nothing secret."

"Check the desk."

The desk was locked. She opened it, glanced through a few files, and shook her head.

"Nothing financial," she said. "No taxes, no books. Couple of Playboys. Toothpicks. Floss. Bottle of mouthwash."

"I'll be done in a couple of more minutes," I said. "I'm almost there."

She walked down the length of the bookshelves, pushing her hand over the tops of the books, feeling behind them. Then she got on her hands and knees and crawled around the perimeter of the room, pulling at the carpet. There was an expensive National Geographic globe in one corner, on its own rolling stand, and when she pushed it out of the way and pulled on the carpet, the corner came up.

"Got something," she said. She folded back the carpet and lifted the board underneath. I stepped over and squatted beside her. There was an old green metal cashbox set in the floor. She popped the lid. Inside were a stack of cash, a chrome-plated.38-caliber revolver, and what looked like legal papers.

LuEllen lifted out the cash and the papers.

"Two thousand," she said, thumbing the cash. She put it back in the box, in exactly the position that it had been. I went back to the computer while she examined the papers. "There're copies of a will and some kind of inventory and divorce papers. You want me to copy them? There's a Xerox out in the hall."

"Do it."

I finished pulling the files from Ballem's computer, shut it down, unplugged the Laplink cables, and started stuffing them back in the black satchel with the portable. I was zipping the satchel when LuEllen came into the room, moving fast, said, "Ssst," and eased the door shut.

"Somebody's outside," she whispered. She scrambled over to her satchel, took out two pairs of black panty hose, and threw one at me. I could hear the outer office door opening as I pulled it over my head. LuEllen, with the panty hose on her head but not yet pulled over her face, was digging in her satchel. She came up with a potato and a gym sock, put the potato in the sock, and stationed herself behind the door. I hid behind the desk.