The security staff were getting ready to shut down the building for the night. The security chief was sympathetic: everyone felt devastated by Bernie’s disappearance, but she wasn’t in the building; I needed to leave.

I got up, my legs so stiff I lost my balance. I clutched the handrail along the wall, my bleary eyes not registering what I was looking at, the shuttered food stands, the garbage that the cleaning crew was shoveling into bags, the aisle numbers going dark as the interior lights were shut off. I was standing near 201, which was blinking at me, the bulb inside getting ready to die.

“Know how you feel,” I muttered.

I had a feverish urge to join the cops and Tintrey Security in driving the city’s streets, the way one does in hunting a missing wallet: it could be here, have you looked there?—even if the police organized a search by quartering the vicinity and fanning out from there they couldn’t cover the buildings, the bridges and tunnels. You need some kind of hint or clue and I had nothing to contribute.

My day had started with Mr. Villard’s shooting. My encounter with the Evanston police seemed part of the dim past, as if it had happened to someone else many decades earlier. I was so worn that I would be more of a hindrance than a creative help in a search. I drove home. Maybe I’d sleep, maybe I’d wake up with an idea.

“Don’t beat yourself up.” I repeated Conrad’s advice as I climbed the back stairs to my place. “Plenty of time for that later. Anyway, Pierre is doing it for you.”

He had looked at me with something akin to hatred, cursing me in two languages for involving his daughter in my criminal affairs. I was so tired that even fear and self-recrimination couldn’t keep me awake. I fell into those fever dreams, where your eyeballs feel scratchy and you only skim the surface of sleep. Viola was chasing me on a Harley . . . Nabiyev was pouring cement over my head . . . Vince Bagby invited me to dinner, then stuffed me into the middle of a mound of pet coke. As the dust closed over me, I saw the light over aisle 201 blinking on and off.

I sat up, completely awake. The slip of paper I’d found in Sebastian’s gym bag had the number “131” scrawled on it with the time. Aisle 131. Be there at 11:30 P.M.

The United Center was on my mind. I stopped in the middle of dialing the phone number for the security chief. Sebastian had been going to see the Cubs, not the Hawks, the day he vanished. Aisle 131, that was Wrigley Field. He’d been meeting someone at Wrigley Field in the middle of the night.

The coaster Bernie had brought home from a Wrigleyville bar. It wasn’t underage drinking that had put those mischief lights in her eyes a week ago—she’d been scouting the ballpark. It didn’t make sense—a week ago, she hadn’t seen the pictures, she didn’t have any reason to think Annie had been there. Maybe she only wanted to emulate Boom-Boom’s and my old bravado in climbing into the park and then after she saw the pictures, decided that was where Annie had hidden her diary.

I dressed in black: T-shirt, warm-up jacket, jeans. Rubbed mascara over my cheekbones to keep them from reflecting light, pulled a black cap over my hair. I tucked my pencil flash and picklocks into my pockets, put on a shoulder holster. Maybe I should leave a message for Jake. Everything I could imagine writing made my errand sound embarrassingly stupid at best. In the end, I scribbled,

Bernie Fouchard disappeared midway through the game. There’s a slim chance she went on her own power to Wrigley Field; I’ve gone off to look for her. Please let Mr. Contreras know as soon as you get up. Also Conrad Rawlings.

I went out the back way, slipped the note under Jake’s kitchen door, then ran down the back stairs as quietly as possible. The dogs still heard me. They were lonely for me and for Bernie; they started barking, demanding that I take them with me. I ran on tiptoe down the walk and was opening the back gate before the light came on in Mr. Contreras’s kitchen. As I jogged down the alley, I heard his gruff voice demand to know who the heck was out there, he had a shotgun, keep your distance.

When I reached Racine, the adrenaline that had propelled me out of bed drained away and I slowed to a walk. My legs felt thick and heavy from the hours of climbing around the United Center and I couldn’t force them into anything faster than a kind of shuffling jog.

The predawn air had a bite in it. The calendar said spring, but under the streetlamps I could see the mica in the sidewalks glinting with frost. I should have worn gloves. My fingers were numb and I needed them to be flexible. I thrust them deep into my jacket pockets and tucked my fists around my thumbs.

The bars along Clark and Addison had finally closed for the night. I had the street mostly to myself. I passed a man inspecting bottles that had been dropped along the street, drinking from any that still had a little something left in them. A squad car slowed, shone a light in my direction. My heart beat uncomfortably—not good to be stopped with a blackened face and picklocks. They played their spot along the street, rested it on the guy on the curb, decided he was harmless, turned south onto Clark.

I walked to the back of the bleachers. Gate L stood invitingly near me, but the wooden doors opened inward, with the lock on the inside, no handles, no place I could insert a pick.

I went back to the wall under the bleachers. Boom-Boom and I had made this climb a dozen times, but never in the middle of the night. And not with the overhang from the new rows of bleachers they’d added. Sometime between my reckless childhood and today they’d also put in new bricks, new mortar. No toeholds.

I used my flash sparingly. Even if I could get to the top of the wall, which was about six feet above my head, I couldn’t crawl past the cantilevers that supported the new bleachers. So near and yet so far.

A rattling in the wire mesh around the stands made me flinch. Night nerves, not good, but I risked a quick look upward with the flash. A piece of newsprint had been blown against the fence. Every time the wind gusted, the edge would slap the chain links.

I walked slowly along the street, studying the wall. Right beyond the gate, the shuttered ticket windows offered the only chance for entry. Not a great chance, but if I could coerce my frozen fingers and tired, middle-aged legs into action, it would do.

I studied the layout carefully, memorizing the distances: I’d have to put the light away and judge it all by feel.

I stuck the flashlight back in its belt holder, rubbed my hands together. The palms were tingling.

I can climb this wall. I am fast, smart and strong. I repeated the sentences, tried to pretend I believed them, grabbed the ledge under the ticket window and wedged my toes against the wall, shifted my hands to bring up my right knee, lost my hold, dropped to the sidewalk.

I am smart, fast, but big. Size is not always an advantage—if Bernie had figured out this route ahead of me, her lithe little body would have floated up like a gymnast’s.

I grabbed the ledge, swung my legs up and fell again. My shoulders and hamstrings were already feeling the strain. Turned around, palms on the ledge behind me, pushed down and jumped at the same time, got my butt inserted into the deeper space left by the window, swung my legs over.

Four inches of ledge supported eight inches of thigh, unstable. I moved fast. Balance beam, yes, we used to jump on a beam no wider than this in high school. I straddled the ledge, pushed myself standing. You can still do this, girl, even if it’s been thirty years.

Light from the streetlamps on Clark provided a dim glow, enough that I didn’t need the flashlight to see where I was going. I started a heel-to-toe walk along the narrow ridge, heading for the brick wall underneath the bleachers.