I SCRIBBLED A STAR next to Ike Quintana's phone number.

"What's your friend's name?" I asked him, pressing the receiver against my ear. But suddenly Quintana was evasive.

"I don't want to say, in case it turns out not to be him," he said. "I have a picture. You can come over and look, if you come now. Otherwise, I have a lot of things to do today."

"Don't you dare leave home! We're on our way!"

I went out to the squad room, said, "We've got a lead. I have an address on San Carlos Street."

Conklin said, "I want to keep working the phones. New videos of the shooting have been e-mailed to our Web site."

Jacobi stood, put on his jacket, said, "I'm driving, Boxer."

I've known Jacobi for ten years, worked as his partner for three before I was promoted to lieutenant. During the time Jacobi and I were a team, we'd developed a deep friendship and an almost telepathic connection. But I don't think either of us acknowledged how close we were until the night we were shot down by coked-up teenagers. Being near death had bonded us.

Now he drove us to a crappy block on the fringes of the Tenderloin.

We looked up the address Ike Quintana had given me, a two-story building with a storefront church on the ground floor and a couple of apartments on top.

I rang the doorbell, and a buzzer sounded. I pulled at the dull metal door handle, and Jacobi and I entered a dark foyer. We climbed creaking stairs into a carpeted hallway smelling of mildew.

There was a single door on each side of the hallway.

I rapped on the one marked 2R, and a long half minute later, it squeaked open.

Ike Quintana was a white male, midthirties. He had black hair sticking up at angles and he was oddly dressed in layers. An undershirt showed in the V of his flannel shirt, a knitted vest was buttoned over that, and an open, rust-colored cardigan hung down to his hips.

He wore blue-striped pajama bottoms and brown felt slippers, and he had a kind of sweet, gappy smile. He stuck out his hand, shook each of ours, and asked us to come in.

Jacobi stepped forward, and I followed both men into a teetering tunnel of newspapers and clear plastic garbage bags filled with soda bottles that lined the hallway from floor to ceiling. In the parlor, cardboard boxes spilled over with coins and empty detergent boxes and ballpoint pens.

"I guess you're prepared for anything," Jacobi muttered.

"That's the idea," said Quintana.

When we reached the kitchen, I saw pots and pans on every surface, and the table was a layered archive of news-paper clippings covered by a tablecloth, then more newspaper layers and a tablecloth over that, again and again making an archeological mound a foot high.

"I've been following the Giants for most of my life," Quintana said shyly. He offered us coffee, which Jacobi and I declined.

Still, Quintana lit a flame on the gas stove and put a pot of water on to boil.

"You have a picture to show us?" I asked.

Quintana lifted an old wooden soapbox from the floor and put it on the pillowy table. He pawed through piles of photographs and menus and assorted memorabilia that I couldn't make out, his hands flying over the papers.

"Here," he said, lifting out a faded five-by-seven photo. "I think this was taken around '88."

Five teenagers – two girls and three boys – were watching television in an institutional-looking common room.

"That's me," said Quintana, pointing to a younger version of himself slouched in an orange armchair. Even then, he had layered his clothing.

"And see this guy sitting on the window seat?"

I peered at the picture. The boy was thin, had long hair and an attempt at a beard. His face was in profile. It could be the shooter. It could be anyone.

"See how he's pulling at the hairs on his arm?" Quintana said.

I nodded.

"That's why I think it could be him. He used to do that for hours. I loved that guy. Called him Fred-a-lito-lindo. After a song he used to sing."

"What's his real name?" I asked.

"He was very depressed," Quintana said. "That's why he checked into Napa. Committed, you know. There was an accident. His little sister died. Something with a sailboat, I think."

Quintana turned off the stove, walked away. I had a fleeting thought: What miracle has prevented this building from burning to the ground?

"Mr. Quintana, don't make us ask you again, okay?" Jacobi growled. "What's the man's name?"

Quintana returned to the table with his chipped coffee cup in hand, wearing his hoarder's garb and the confidence of a rich man to the manor born.

"His name is Fred. Alfred Brinkley. But I really don't see how he could have killed those people," Quintana said. "Fred is the sweetest guy in the world."

I CALLED RICH CONKLIN from the car, gave him Brinkley's name to run through NCIC as Jacobi drove back to Bryant Street.

Chi and McNeil were waiting for us inside MacBain's Beers O' the World Pub, a dark saloon sandwiched between two bail-bond shacks across from the Hall.

Jacobi and I joined them and ordered Foster's on tap, and I asked Chi and McNeil for an update.

"We interviewed a guy at the Smoke Shop on Polk at Vallejo," said Chi, getting right into it. "Old geezer who owns the place says, 'Yeah, I sell Turkish Specials. About two packs a month to a regular customer.' He takes the carton off the shelf to show us – it's down two packs."

Conklin came in, took a seat, and ordered a Dos Equis and an Angus burger, rare.

Looked like he had something on his mind.

"My partner gets excited," said Cappy, "by a carton of cigarettes."

"So who's the fool?" Chi asked McNeil.

"Get to it, okay?" Jacobi grumbled.

The beer came, and Jacobi, Conklin, and I lifted our glasses to Don MacBain, the bar's owner, a maverick former SFPD captain whose portrait hung in a frame over the bar.

Chi continued, "So the geezer says this customer is a Greek guy, about eighty years old – but 'hold on a minute,' he says. 'Let me see that picture again.' "

Cappy picked up where Chi left off. "So I push the photo of the shooter up to his snoot, and he says, 'This guy? I used to see this guy every morning when he bought his paper. He's the guy who did the shootings?' "

Jacobi called the waitress over again, said, "Syd, I'll have a burger, too, medium rare with fries."

Chi talked over him.

"So the Smoke Shop geezer says he doesn't know our suspect's name but thinks he used to live across the street, 1513 Vallejo."

"So we go over there -" Cappy said.

"Please put me out of my misery," Jacobi said. His elbows were on the table, and he was pressing his palms into his eye sockets, waiting for this story to pay out or be over.

"And we got a name," Cappy finished. "The apartment manager at 1513 Vallejo positively IDed the photo. Told us that the suspect was evicted about two months ago, right after he lost his job."

"Drumroll please," said Chi. "The shooter's name is Alfred Brinkley."

It was sad to see the disappointment on the faces of McNeil and Chi, but I had to break it to them.

"Thanks, Paul. We know his name. Did you find out where he used to work?"

"Right, Lieu. That bookstore, uh, Sam's Book Emporium on Mason Street."

I turned to Conklin. "Richie, you look like the Cheshire cat. Whatcha got?"

Conklin had been leaning back in his chair, balancing it on its rear legs, clearly enjoying the banter. Now the front legs of his chair came down, and he leaned over the table. "Brinkley doesn't have a sheet. But… he served at the Presidio for two years. Medical discharge in '94."

"He got into the army after being in a nuthouse?" Jacobi asked.