"This is Sparky," the lab director said to a normal human. The boss opened my cubicle. "Sixteen years old and eager to find a master. He fits your specifications."

I stood and smiled, forcing myself not to quiver with delight.

"He has the advanced gene suite," the swarthy director said. "Great mind, physically quick, outgoing, and only a touch of ferocity."

I was so pleased that he approved! The men who fed and trained us liked me, and the teacher of the human syllabus rated me highly, too.Was this other normal to be my permanent master?

"Has he the full subservience gene set?"

The buyer was black-haired and thin, three or four centimeters taller than me. He'd probably been "improved" as a zygote. No obesity or addiction genes; boosted intelligence, and extended life.

"All our hybrid products have the taming genes," the director replied.

He stroked the yellow-and-white cap of hair on my head. He ran his finger over the slightly broad base of my nose, which, I'd been told, contained a larger-than-human "olfactory bulb."

"Sparky is one of our premier, enhanced specimens, and he can pass."

"I don't want him sniffing around women in my tower. He will pay attention to the briefing, obtain a document, and deliver it to me quickly."

"If you wish, I'll review with you the line of Labradors from which we took many of his special genes," the director responded. "All faithful retrievers, all obedient and loving."

I nodded vigorously. "I'll be reliable, sir."

The master shook his finger. "No talking without permission!"

I ducked my head and stepped back. A "cower" is what my trainer called the reaction. He said it gave me away as a genetic cross.

"Why do you call him Sparky?" the customer asked.

I walked over to the wall, pointed at the electric switch, and squeezed the eel electroplaques in my left index finger. Ping! A high-voltage arc formed and the overhead light went out.

"That capability will be handy for the robbery you contemplate."

"I didn't say that was my purpose," the customer snapped.

I smelled his rage pheromones and wanted to cower again. The laboratory technicians did design and train me to steal. In addition to my special hybrid talents, I possessed nimble fingers, an athletic body, and could read building schematics, tap into police Web circuits, and pick pockets.

"He can see in the dark?"

The boss nodded. "At night he doesn't need much beyond the IR everything gives off. We've also supplemented Sparky's cortex - coupled with minor inner-ear adjustments - so he has some sonar capability."

"He's wildly expensive. How about a short-term lease?"

"We don't deal with crossbreeds more than once. These sidelines are illegal, you know."

I found myself close to the buyer again, smiling at him, my mouth open and panting a little. Please buy me, I thought. I'll love you.

We left together. In the car I put my nose against the window seal, stared, and slid from one side of the back seat to the other. A first time out!

At that, my new master used the switch the trainer had given him. More than once.

Later, on the throw rug in his utility room, I guess I wept a little.

"If you're caught," my master said the next morning, "you'll not describe me, hear?"

"Yes, sir."

I sat on the couch in his penthouse living room while he paced. Outside, the sky was cloudless. Occasional flutter-bug transports whizzed past to nearby tower platforms. The multishaded blue buildings and the vapor-trailing pastel vehicles were new to me. I liked his gorgeous red-and-blue-patterned rugs and the furniture that changed shape on command.

"Don't believe threats by the police to make you talk," he added. "It's illegal to torture even animals."

"Yes, sir."

"Come," he ordered and turned to the inner wall. Glass-enclosed shelves protruded. He switched on a set of internal lights. "Do you see these?" Three yellowed, handwritten documents lay widely separated, double mirrors reflecting their undersides. "Louise Chamond has another letter of this Abraham Lincoln series and I want it!"

When he came in that second night to see if I had cleaned my dish, I dared ask, "Sir, you won't terminate me after I succeed, will you?"

"You don't fit into my long-term plans. Better not remind me."

"But ninety-eight percent of my genes are the same as those of all humans."

"True also of a chimpanzee." He slashed me across the face with the switch. "Don't be impertinent. You'll learn your fate when it happens."

The next night, in my skintight gray jumpsuit, I paused in the central air-conditioning duct as it rose to the first floor of Ms. Chamond's building. I breathed deeply and sounded "chirp" from high up against my palate. The reflections from the high-frequency sound waves created for me an image of a corner platform in the turn before the duct climbed to higher floors. Security system electronics, I guessed. Motion and nonambient IR detectors, for sure, but no sound trap because of the building's thin interior walls.

Balancing with my toes on an aluminum brace, I reached up cautiously and felt for the next section's cross member. Then I lifted my body a meter and found another brace. I gradually straightened, chirped, and studied the shelf from closer in. Two insulated sets of wires fed through a grommet in the duct, divided, and then led to sensor arrays. One wire set was for electrical power, and the other would return signal. I slowly extended my arm and then my index finger so it barely crept over the shelf. I "pinged" the signal leads, making sure my current flowed outward to the sensors.

At the third story, where the duct branched out to send cool air to the four apartments and hall, I lay flat, suppressing a shudder at the tight quarters, and rested.

Good sense said I should "turn feral" and escape the cruel master. But I belonged with a human.

I sighed and started climbing again. At the twelfth floor, I encountered a second alarm installation, and then one at every floor above. After silencing a shelfful of arrays and antennae between the fourteenth and fifteenth stories, however, I turned north at the next duct junction and crawled above my target apartment.

Fifteen minutes to gain the letter, I thought, and then I'll slide back down the duct. With the security systems already inactivated, descent would be easy.

Maybe my master will be so pleased, he'll . . . I swore at myself.

Squeezing my shoulders together, I eased through a junction of even smaller ducts and crawled down the one I picked out on my master's schematic. Careful to remain silent, I peered down through a louvered air-conditioning screen and saw a dark room containing a disconnected robotic maid, a stand-up spot vacuum, and, in the corner, what looked like a washer and dryer heaped with clothes. A large sink stood across the room.

Ugh! Ammonia vapor stung my nostrils and seemed to anesthetize them. Liquid puddled in front of the sink from a knocked-over bottle. Luckily, since I had climbed an air-conditioning intake duct, I hadn't fought the stench all my way up through the building.

I lifted the screen and pushed it down the duct, then dropped headfirst into the room, rolling into a somersault as I hit the floor. Barely a thud, I thought. But I'd put my foot into the pool of goddamned cleanser.

Suddenly, a weight dropped on me. Flattened, on my stomach, and my lungs knocked empty of air, I felt a cold, sharp knife-edge against my throat. Someone sat on my back with knees alongside my waist.

"Stay still," I heard, "or I'll cut your throat."

The ammonia had masked her pheromones while she waited in the corner, on the washer and dryer.

"How did you know I was coming?"

She snorted. "Watchdog genes. I was bought to protect this vacant place against interlopers like you."

She'd heard me slide along the duct. Ears as good as mine. I could smell her now, under the cleanser. Nice.

"How about a fair fight?"

"I've German shepherd ferocity and you're only a bird dog, I guess." Then she laughed. "But why should I give up my advantage and let you try to be lucky?"

"My master will terminate me."

She removed the knife from my throat and sat back.

"Failure or success," I said, "he'll terminate me. I've about decided to run."

"You'll wither from guilt."

My lack of reply was agreement, I guess.

"My name is Beauty," she said, and stood. "No robbery, now."

When I rolled over and looked up at her, I realized her name fit her. Black hair, ivory complexion, and below a wide nose similar to mine, a full-lipped mouth twisted in an "I'm better than you are" grin.

But yellow, animal eyes.

She had a straight back and curves barely constrained by a one-piece, dark-blue exercise garment. She'd tied her hair back so her left ear was exposed. A shell-like, pink ear.

"Please show me the document my master wants," I said and stood, too. In the apartment, she commanded the lights to turn on. Pastel walls lined her mistress's home. Mauve rugs with pink highlights, lavender sofas, overstuffed chairs, and pale-green curtains furnished it.

Beauty pointed to a bank of glass cases and put her back against a wall. She still brandished the knife and was slightly bigger than me.

Stepping over to the labeled case I wanted, I spotted the document, skimmed its salutation and introductory paragraph, then read out loud: "Laws permitting slavery or involuntary servitude shall be null and void within the United States of America."

"I understand Lincoln wrote that before his successors drafted what they call the Thirteenth Amendment," Beauty noted.

"Doesn't apply to us, of course," I replied. "Our servitude comes from centuries of animal selection and then transfer of our genes to human germ cells, not from laws."

Beauty glanced away, although her nostrils flared a bit and her cheeks became tinged with pink.

"It is possible to break the bond of subservience," she whispered. She bit her luscious lower lip and furrowed her ivory brow. "Not that breaking it does much good. You transfer loyalty by staying away from your master and near someone else who feeds and houses you. Lots of whimpering while the change takes place. We've both been undergoing this transfer since we left our labs." She shrugged again and looked away. "But we only exchange one master for another."

She sniffed again. So did I.

Suddenly, an idea crystallized. "Bond yourself to me," I said. "If we stay together for a while it'll become permanent."

Beauty lifted her head and frowned.

"The Labrador in me will worship the human in you," I explained, "and the shepherd in you will love the person in me. We can break forever our involuntary servitude to normal humans."

Beauty trembled.

"I already love you," I said. "You're my new boss."

Beauty straightened, apparently forcing her muscles to steady.

I moved forward a step. "Concentrate on me," I said. "I'm your new master."

Beauty took a deep breath and then slipped the knife into a sheath at her side. Her mouth quivered.

I stepped forward again and grabbed her hand. Beauty's eyes were wide. She seemed almost hypnotized by mine.

"Instead of involuntary servitude," I said, "we'll have willing slavery. We'll stay together for our lifetimes and laugh at people who try to master either of us."

I felt sorry for normal humans, who would never experience animal love.