He should have known it was too good to last. Abby had been too quiet lately, too..well, the only word he could come up with was well-behaved. Which didn't fit, but then, nothing did where Abby was concerned.

Work had been a little slow--somehow--and the last he'd seen of her she'd been creating a model of the Battle of Bull Run out of spare lab supplies. He'd decided not to interfere; if she was staying busy, she was staying out of trouble, and a bored Abby could find trouble more easily than anyone else he knew.

So he'd gone back to the bullpen, where Tony was pretending to work, McGee was doing something that resembled work, and Ziva was hitting keys with enough force to make him fear for the keyboard. He decided not to interfere with that one, either.

The quiet lasted through most of the morning, but then some package came in that had to get to Abby--some program she'd been waiting for or something. "DiNozzo," Gibbs said, looking up. "Go take that to Abby."

"Sure thing, Boss." Tony picked up the package and headed for the elevator.

But he returned a few minutes later, still holding the package. "I couldn't find her, Boss," he said, looking perplexed.

"She's in her lab, DiNozzo. How is she hard to find?"

"She's not there," Tony insisted. "I looked!"

Gibbs rolled his eyes. "This better not be some kind of practical joke, DiNozzo," he warned Tony.

"Boss, I swear to you, she is not in the lab. Or Autopsy--I called Ducky." Tony looked at the package in his hand. "I don't know where she is, but she's not there."

"Uh huh. Let's try this again." Gibbs stood up and pointed to the elevator; with a sigh, Tony followed him down to the lab.

Gibbs was surprised--and wary--to see that Tony was right. Abby was nowhere to be seen. Her lab coat was tossed over her counter, there was a half-full Big Gulp by her keyboard, the music was blasting--or it was until he hit the button--but Abby was nowhere in sight. He looked around carefully and didn't see any sign of her...but her boots were neatly lined up in the corner and he was willing to bet her clothes were hidden as well.

"Oh, hell," he said under his breath. "Not again."

She hadn't done this in ages--at least, not that he knew of. And he'd hoped...but that was too much to ask for where Abby was concerned.

"Abs," he called, turning around in a circle. "Abby..."

"Mrrow!" A sleek black form leaped at him from the top of a supply cabinet; Gibbs barely caught the cat in time. It butted its head under his chin, purring loudly, and he adjusted his hold to keep it secure in his arms, scratching its ears.

"Um, Boss?" Tony looked at the cat, confused. "How did a cat get in the lab? And what is it doing here?"

"She," Gibbs said wearily, petting her. "It's a female."

"Okay. What's she doing here, and how did she get in here?" Tony reached out gingerly to pet the cat, scratching under her chin. She purred louder and leaned into his touch. "She's beautiful, Gibbs."

"Yeah. And she knows it." Gibbs sighed and tried to put the cat down, but she dug her claws into his shirt. He let her stay, glaring at her; she just gave him a feline smile and purred.

"Seriously. Pure black, except for that one white paw and the tip of her tail--I've never seen a cat like that before." Tony flicked the cat's tail; she sneezed delicately and rubbed her cheek along Gibbs' neck, scent-marking him.

"And you probably never will again." Gibbs glared at the cat. "This isn't funny," he told her.

"Um, Boss?" Tony sounded like he thought Gibbs was smoking something.

"You were looking for Abby?" Gibbs said wryly. He nodded at the cat in his arms, contentedly kneading his shoulder. "You found her."

"Boss..." Tony shook his head. "That's a cat."

"I know that, DiNozzo. I'm not blind."

"Last I checked, Abby was human." Tony eyed them both warily.

"Last you checked, she was." Gibbs sat down on Abby's stool, letting the cat settle in his lap. She began kneading his thigh instead, sounding like a motorboat. "And most of the time, she is."

"But not now." Tony leaned against the counter and looked at the cat. "Okay. Assuming I believe you--and that's a pretty big if right now, Boss--why would she do this?"

"Hell if I know, DiNozzo! Do I look like an expert on people changing into cats?" Gibbs glared at him. "It's completely voluntary, both changing and changing back, so for whatever reason, she wanted to. She hasn't done it in a while, that I know of--last time I remember..." He trailed off, remembering the last time Abby had gone feline on him.

"When was that?" Tony asked.

"After Kate died," Gibbs said quietly.

"But she was here during the day!" Tony protested. "Remember? She worked the case?"

"Exactly, DiNozzo. During the day. At night, I had to take her home with me. She stayed feline at night for a full week--and an entire weekend, when we had that time off." Gibbs sighed. "I don't know if something's upset her this time or if she's just bored."

"Nothing's gone wrong lately," Tony pointed out. He reached out to scratch under her chin, making the cat close her eyes and purr in feline ecstasy. "You think she'd change because she was bored?"

"She's done that before," Gibbs said wryly. He looked down at the cat--he was not going to call her Abby--and sighed. "What the hell am I going to do with a feline forensics expert?"

"We can't convince her to change back somehow?"

"If you've got an idea, DiNozzo, I'll be glad to hear it." Gibbs looked down at the cat. "Damnit, Abs, why do you do this to me?"

The cat just yawned and closed her eyes.

Tony looked around the lab, frowning. "Wait," he said slowly. "I have an idea."

"What?"

Tony grinned. "If this doesn't work, nothing will." He picked up Abby's Big Gulp and went over to the sink in the corner, taking off the lid. "Abs," he sing-songed. "Abby..."

Slowly, he began to tilt the plastic cup. A black streak launched itself across the room and a very human Abby slammed into Tony, stealing the cup and managing not to spill a drop. "Do not," she warned him, "mess with the caffeine."

"Right." Tony sounded a bit strangled, and from the force with which she'd hit him, Gibbs could see why. His own lap hurt from where her claws had dug in before she'd leapt for Tony.

"I was just bored," she complained, turning to Gibbs. "I'd have turned back if there was work to do."

"You can't just change into a cat at work," Gibbs said, looking anywhere but at her. "And Abs, could you put your clothes back on?"

She blinked, then looked down. "Oh. Right." With a complete lack of self-consciousness, she began pulling her clothes on, fastening her boots and adjusting the chain belt around her waist. "That better?"

"Much. Thank you."

"I don't know," Tony teased. "I kind of liked--oof!" He doubled over, coughing; Abby smiled sweetly and patted him on the back.

"Elbow in the solar plexus will do that to you," she said cheerfully. "So." She turned to Gibbs and pointed her index fingers at him. "What can I do for you today?"

He rubbed a hand over his face and handed her the package. "That came in for you. Have fun. And don't do this to me again, okay?"

"But you know right where to scratch," she complained.

"Abby--" Now it was his turn to sound strangled.

"I didn't mean it like that!" She turned on him, eyes wide. "Honest, Bossman!"

"I believe you. But just...don't do this again. At work." Gibbs tweaked a pigtail. "Okay, Abs?"

Abby sighed theatrically. "All right," she said glumly.

"C'mon, DiNozzo. Let's go back to work." Gibbs headed for the door, Tony following.

To his credit, Tony waited until they were in the elevator to say anything. "Boss, that--"

"Yes."

"And she--"

"Uh huh."

"And--"

"Yeah." Gibbs raised an eyebrow at him. "So?"

"So..." Tony shrugged. "Cool."

Well, it was a better reaction than he'd been hoping for. "Good." The doors dinged and as they slid open, Gibbs smacked him upside the head. "But don't ever mess with Abby's caffeine again."