A helicopter with a searchlight is hovering low over Prospect Park, its juddering hum reminding Lourdes of a man deciding how to respond to an insult.

As she approaches the Fifth Street entrance, she sees ambulance guys smoking cigarettes, in no big hurry to do anything. Yellow tape cordons off the bike lanes, a big crowd behind it already, bathed in flashes of blue, white, and red from the squad car lights. An exclusive nightspot for people you wouldn't want to party with: white-shirted supervisors, regular uniform cops, and detectives in off-the-rack suits.

On first glance, it looks like the unusual event they've shown up for is a vacant parking space in No-Park Slope. But then she sees the fleecy white and red clumps, which turn out to be feathers, trailing back toward the sidewalk. They lead past inside-out latex gloves, snipped rubber tubing, and a bent syringe to a body facedown near an elm tree, stuffing coming out through the ruptured stitching of a Canada Goose parka.

Lourdes flips tin at the cop standing guard and ducks under the tape, not liking the way her trousers crackle with the bend. A month without carbs and she still can't get under 165. But fuck it, she's bootylicious and proud. Always been a big girl, with lots of bounce to the ounce. All creamy café con leche abundance busting from a halter top when she was waitressing undercover at the Golden Lady Gentlemen's Lounge, substantial and serious when she's wearing her Lane Bryant business suit in the squadroom. Either way, whoever couldn't appreciate that rearview had no class and could just move it along, nothing to see here, fellas.

"Detective Robles, welcome back." Captain Bowman, the CO from her patrol days, is just inside the tape, shivering in the spring chill. "I'll cue the balloons."

She smiles and bunches her cheeks up like brioche tops. Three months back in the detective squad and still catching grief from the trolls downstairs. What else could she expect? Even before she got in trouble, she'd been dangerously low on allies at the seven-eight. Pretty much everyone she used to work with had been pissed about her getting to jump the line before she'd even completed her eighteen-month rotation in Narcotics.

But none of them happened to be getting highlights at the Sophisticated Lady Hair Salon on Flatbush Avenue when a five-time loser named Tyrell Humphries tried to hold the place up with a .22, which he dry-clicked twice upside Lourdes's head after she ID'd herself as a cop. Somehow even with a smock on, she'd managed to wrestle the gat away before shooting him in the ball sack. Which, in turn, led to her getting promoted at a special ceremony attended by the mayor and the PC.

Her photo appeared in the Daily News, effectively ending her career as an undercover. And leaving her unprotected six months later when her fuckwit partner, Erik Heinz, got caught on a cell-phone camera verbally abusing an Arab cab driver for cutting them off on Ocean Parkway, with Lourdes standing behind him, silent and embarrassed. The clip became an instant YouTube sensation, seventy-five thousand clicks in the first three hours, earning Heinz a new assignment moving Staten Island barricades and Lourdes six weeks in a VIPER room, watching security monitors in a housing project basement. When she got out, she was no longer known as the "Heroine of the Hair Salon," but as "that fat girl who got in trouble."

"What do we got, Captain?"

"Deep breath, LRo. Taxpayer down."

"White guy?"

"Amazing. You're getting called in six hours after your tour ends and you figure that out on your own. No wonder they let you hang on to that little gold shield."

Four detectives from her squad are already at the scene, joining a couple of medical-legal investigators from the ME's office in Tyvek suits and booties. Two CSU techs take photos and make notes. The ghouls are parking the morgue van over by the parks administration building. She notices that every time she catches someone's eye, it darts away.

"The 9-1-1 operator patched the call through a few minutes past eleven," Bowman says. "Residents across the street reported hearing shots."

Lourdes looks over at the limestones and brownstones on the other side of Prospect Park West, lined up like nineteenth-century novels you needed perfect ACT scores to read. Each worth four million easy these days — more, if you could get a dentist or a shrink paying office rent on the garden floor.

It must be twenty years since the last murder in the park that white people cared about. A drama teacher got shot for his mountain bike near Swan Lake, back when she was in fifth grade and Brooklyn was still fierce.

Nowadays, the whole damn park is an ad for healthy urban living. At least when the sun is up. Private foundations and citizen volunteers had poured dollars and hours into protecting the trees, saving the ducks, bringing in the Metropolitan Opera, and chasing junkies from the band shell. Any Saturday or Sunday, the six hundred acres are fields of well-tended flesh: world-class runners, Tour de France wannabes, Audubon Society bird freaks, Olympian volleyball players, and Ivy Leaguers dragging their $500 congas to the African drum circle in the grove.

At night, though, the ghosts still come out. The Picnic House gets shrouded in mist like a castle from some old Shakespeare play. Homeless people still hide out in encampments in the woods, where they can lie down quietly with their sorrows in the moonlight. The occasional wolf pack still roams over from Parkside Avenue or Empire Boulevard. Every few years, a ninja with a sword shows up in the Vale of Cashmere, a vengeful spirit from the eighties slashing at gay men in the bushes. And every season or two, a lonely life still ends dangling from a low branch on Suicide Hill.

"See all the fluff that came out of the coat?" Bowman points out the wisps blowing away. "Must have been a big gun."

"Or defects in the nylon." Lourdes aims her chin at a flagrant rip in the stitching. "Eyewits?"

"The good news is, we found some screwball with a sleeping bag and a view of the crime scene just on the other side of the wall."

"The bad news?"

"He's not talking." The captain jerks a thumb over his shoulder.

Detective Robert "Beautiful Bobby" Borrelli from her squad is a few yards away, gesturing haplessly at a man wearing a hat with furry ears and a plastic shower curtain over his shoulders.

"It's not clear he speaks English," the captain says. "Or any other earth language."

"Like that matters." Lourdes unbuttons her coat as she strolls over. "What up, B.B.?"

Beautiful Bobby, Romeo-eyed with a Guido Elvis pompadour and a small pink baby butt of a bald spot, shrugs at his subject.

"Mork from Ork here. Ten minutes, no ID, no hablo. He's either deaf and dumb or thinks we're from the intergalactic border patrol."

"I'll talk to her," the homeless man says matter of factly.

"See that, B.B.?" She throws her shoulders back. "It's all about the attitude."

"I know you." The homeless guy adjusts the shower curtain like an aristocrat's cape.

"You know me?"

She studies the homeless dude more closely. He has the face of an Aztec warrior debauched by years of hard city living: high, bruised cheekbones and slanting almond eyes with tiny globs of mascara sticking to the lashes.

"I met you in the park," he says, with a hint of a Mexican accent. "Long time ago."

"Yeah?"...