A/N: Oookay...only one reviewer to thank...THANK YOU,leath! Yes, there will be a lot of Abby - in fact, I do believe you'll be surprised by just how much Abby there is. Also thanks to ladyyuuki16, andrewjeeves, and cms4ever for putting this story on alerts...I would love to hear some feedback from you guys once in a while too.

Now, on with the story!

Chapter One

09:30, October 31; NCIS Headquarters, Washington, D.C.

Tony absentmindedly twirled a pen around in his fingers, his eyes fixated on Ziva making a phone call at the opposite desk. Her left hand cradled the phone against her ear, while her right was busy jotting down notes. Her clothes were ordinary, nondescript – navy blue, three-quarter-sleeved blouse and black capri pants – and she had tied her dark hair back in a half ponytail, leaving the other half down to soften her face.

But there was something odd about the picture today, and it was driving Tony crazy trying to figure out what it was that was different about the ex-Mossad agent.

McGee, looking up from his monitor, noticed Tony's concentration, and he followed his gaze to Ziva. A smirk made itself known on his face; Tony was at it again.

The two could dance around the subject all they liked – but everyone knew Tony and Ziva were perfect together. They were just too damn stubborn to admit they liked each other. McGee and Abby actually had a bet on; he didn't believe Tony would ever work up the guts to tell Ziva how he felt, but she cheerfully pointed out that if Tony didn't take the first step, Ziva would. Ducky heard about the bet from Palmer – who wagered that it wouldn't happen at all – and he seriously predicted that they would realize what they meant to each other…eventually.

So far, nobody had won the bet, as they hadn't set a time limit for it.

Still, that didn't mean McGee couldn't make fun of Tony.

"If Ziva catches you staring at her like that, she'll kill you," he said. "You know that, right?"

"Shh!" Tony shushed him. McGee smirked.

"What are you looking at, anyway?"

Tony swirled around in his swivel chair. "Does she look different to you today?"

"Different?" McGee sneaked a cautious glance at Ziva. "No…"

"She looks different to me," Tony said.

McGee hid a smile – that is, until Tony began wondering out loud about the difference.

"Let's see…it's not her hair, or her face…it's definitely not her clothes…maybe it's her makeup? No, Ziva hardly wears makeup. Okay…think, DiNozzo, think."

"Tony, do you mind keeping it to yourself?" McGee asked pointedly. "I'm trying to find Kendall Wilcox."

"Any luck on that?"

"Not yet."

"Wonder if the CSIs got anything extra," mused Tony, switching track abruptly.

"We'll know as soon as Ziva gets off the phone," McGee replied as he clicked his mouse. A short beep emitted from his computer, and, on cue, Gibbs entered the area, a cup of coffee in his hand.

"Got something, McGee?" he questioned.

McGee regretfully shook his head. "Nope. Sorry, boss. It's just an alert system I set up on my computer for…well, doesn't matter what it's for."

Just then Ziva put down the phone with an audible clatter. "That was Detective Messer from the New York Crime Lab. They've been searching for Vincent Wilcox, but they haven't managed to find him yet. Meanwhile, they're keeping tabs on Janice Bright and investigating Judge Harvey Gates' murder. They've also got a protection detail on Linnaeus and Marie Wilcox, just in case anyone might decide to try attacking them because of their connection to Bright or the smuggling ring."

"So we've got nothing," Tony surmised.

"Not exactly," said Gibbs, already moving to the exit. "Dead Marine downtown, let's go."

As the NCIS agents geared up with practiced movements, Tony kept one eye on Ziva and suddenly realized why she looked different.

"Oh, now I see it," he said, his tone full of self-satisfaction.

"See what?" Ziva queried as she tucked her gun into her waistband.

"You're wearing the necklace I gave you last Christmas – or were we counting it as Hanukah?"

Ziva scoffed. "That is why you were staring at me for the past twenty minutes?"

Tony blinked, right before he cringed. "You saw that?"

Ziva simply smirked at him as they got onto the elevator.

Major Daniel Wells was not a particularly distinguished Marine, but he was a Marine who did his work well. He clocked in punctually, gave notice when he was going to be absent, and had an earnest, honest attitude about him that his commanders loved. He had made friends with his entire unit, and his superiors had never had to report him for misbehavior. On all accounts, he was a well-liked, well-behaved soldier whom no one would want to kill.

The only problem with that conception, of course, was that someone had killed him. Killed him and left the knife sticking out of his chest, pushed in to the hilt.

"I'm not buying it," Tony declared. Ziva rolled her eyes.

"Here we go again," she said.

"You can't be a Navy Major and not have any enemies," Tony pointed out.

"Maybe," Ziva conceded, "but he hasn't been off base in months."

Tony harrumphed. "What I don't get," he said, "is why we're investigating this case when we've still got a major homicide to solve."

"We do not have any new leads on the Jasper murder, and the judge's homicide is out of our jurisdiction," Ziva reasoned. "Until something new comes up, instead of wasting time chasing down nonexistent leads, we can solve other murders."

"She's right," McGee put in from where he was snapping photographs of Daniel Wells' dead body.

"No duh, McGoo."

"Greetings to you, my fellow rabble-rousers, on this fine day of tricks."

Tony, Ziva, and McGee turned to see Ducky making his way over to them with his assistant Jimmy Palmer.

"I'm guessing that's your way of wishing us Happy Halloween?" Tony deduced.

"You are correct, Anthony," Ducky said with a chuckle. He set his portable kit down on the ground next to him as he squatted to perform a preliminary examination of Wells' body.

"Have you seen Abby's costume this year?" Palmer asked, looking, as always, like a sweet world-class nerd. "It's awesome."

"Yep," McGee agreed.

Tony frowned slightly and checked his watch. "It's 10:22 right now; you've only been at work since 8:30, and you were on our floor the whole time. When did you get a chance to see what Abby's wearing?"

McGee just smirked at him, leaving Tony puzzling over this.

"Got a TOD, Duck?" Gibbs inquired, appearing on scene just as Ducky pulled a liver thermometer out from their victim.

"Liver temp is 89.9 degrees, which puts time of death a little less than six hours ago," Ducky replied. He tried pulling the dead major's arm up; it fought him, and the movement stopped about six inches off the ground. "Rigor is well set in."

"So what do we know, boss?" Tony asked.

In response, Gibbs just handed him a handwritten address; Tony accepted it.

"Okay, so this is…what? – brother, wife, best friend?" he questioned. "Mother-in-law?" he added jokingly.

"Sister," Gibbs replied. "Take Ziva with you."

"Yes, sir," said Tony, already moving – while Ziva tried to figure out whether being stuck with Tony on Halloween day was a blessing or a curse. "Come on, Ziva – let's go trick-or-treating for information."

Ziva rolled her eyes as she followed him.

Curse. Definitely curse.

When McGee reached Abby's lab later, as usual, there was loud music blaring from her wall-mounted speakers. McGee had to shout to get her to notice him over the din.

"Abby!" he yelled.

"Oh, sorry, McGee." Abby hastily turned down the volume and spun to face him with a bright smile. "What's up?"

Abby Sciuto was well known throughout the office for her elaborate costumes on Halloween Day, and this year was no different. This time, she had decided to take on the superhero branch of crime-fighting and had donned a silky black Batgirl costume, complete with a cape and a pointy-eared mask-hood that was currently pulled down over the upper part of her face.

"Have I mentioned I really love that costume?" McGee asked with a grin. Abby grinned back.

"You did, this morning."

"Speaking of which, I accidentally let it slip that I'd seen you in it, even though I've been upstairs since I got to work."

"Ah," said Abby. "So, am I going to have any curious colleagues asking questions?"

"Probably just Tony."

She nodded, smiling. "I can handle Tony." She pulled the hood down, revealing her cheerful face and black hair tied in a low ponytail instead of its usual two high pigtails. "So, what've you got for me?"

McGee handed her the knife from Wells' body, now encased in its own plastic evidence bag. Abby looked disappointed.

"That's it?" she asked. McGee smiled.

"For now," he replied. "Ducky's starting on the autopsy as we speak, so we'll have more for you soon."

Abby's face brightened once more. Then she asked, "Okay. Now, what are you hiding behind your back?"

McGee pulled his left arm from where he'd been keeping it behind him. "What, this?" he asked, shaking a large Caf-Pow in front of her.

Abby's grin grew wider.

Ducky carefully unbuttoned Daniel Wells' bloodstained shirt with practiced hands, then slid it off his torso in smooth movements.

"Mr. Palmer, would you get Mr. Wells' belt for me, please," Ducky requested.

"Sure thing, Dr. Mallard," Palmer agreed, sliding his hand to Wells' belt buckle. He unfastened it, and then he and Ducky slowly pulled Wells' pants from his legs.

It was then, when Daniel Wells lay almost naked in front of them and there were no clothes to conceal him, that Ducky noticed what he had previously missed. The ME inhaled sharply, attracting Palmer's concerned attention.

"Dr. Mallard?" he inquired, still holding Wells' pants.

"Mr. Palmer, get Gibbs on the phone," Ducky instructed.

"But we haven't even started the autopsy," Palmer protested.

"Just do it, Mr. Palmer. There's something on our dead Marine he needs to see."

Because, carved right there on Wells' ankle, Ducky was staring at a bloody red 'M'.

A/N: So, updates from now on will be daily, as usual. Need I even say that I'd love to hear what you have to say?