I miss ninja Ziva from Seasons 3, 4 and 5. She hasn't had a fight scene for ages – not counting her spat with Liat – and those were my favourite parts. This is just me resurrecting the old Ziva in what I hope is a believable way – she would not just suddenly switch into assassin mode – I have tried to keep in character.

The lift doors beeped to signal the arrival of the tardiest member of the team. Tony hurried through the throng of people crowded into the small area. He pushed past agents from various agencies before arriving at his desk.

'What's going on?' he hissed across the bullpen to his partner.

'Maybe if you got here on time, you would know,' she replied.

He raised his eyebrows and pressed on. 'I had something important to do. What is going on?'

'Last night there were fifteen assassinations of Marines in DC,' Ziva told him.

Tony snorted. 'Have to do better than that to fool me, Ziva,' he informed her.

She rolled his eyes and crossed over to face him across his untidy desk. 'Not everyone is like you, Tony.' She wrinkled up her nose to exemplify her point. 'Some people can just say things.'

He cocked his head and studied her for any carefully controlled smirks. He found no signs of jest and his eyes widened. 'Fifteen?' he asked incredulously. She nodded. He frowned and scanned the crowd he recently barged through. 'Why are other feds here then?' he inquired.

Ziva leant forward. 'There were also four civilians killed in the same way.' Her voice was calm but Tony registered the slight tension beneath her steely exterior. Memories of assassinations flooded her mind and the garish orange room disappeared, replaced by dusty streets saturated with blood.

Tony leant towards her as well so that he could feel her hitched breath on his face. 'Where's Gibbs?' he asked loudly to retrieve her from her reverie. Her eyes shifted uneasily before resting on his face which was filling up her view. She shrugged and pulled away. 'Where's McGeek?' he probed, not wanting her to resurrect her guarded attitude. She smiled despite herself at his persistency.

'With Abby.' Her nose twitched. 'He did not like the crowds descending on our office.' Tony smiled.

'Sounds like McGee,' he confirmed. He finally dropped his jacket on the floor and came out from behind his desk to join Ziva in the middle of their space. 'Gibbs must be somewhere,' he remarked. The bullpen seemed to be the only space free from the throng of outsiders and the most obvious explanation for that was them avoiding the wrath of intruders from Gibbs.

'He is,' came a gruff voice behind them. Tony spun round and was confronted with Gibbs.

'Boss,' he exclaimed in a phoney cheery voice trying to dispel the look of distinct displeasure on his esteemed boss's face. 'First coffee break of the day?' he asked gesturing to the half empty coffee cup in Gibbs's hand.

Gibbs narrowed his eyes warningly and Tony retreated behind his desk once more. Gibbs nodded towards the gaggle of chattering agents and glanced at Ziva questioningly. 'They still here?'

Ziva smiled at the disgusted tone and nodded.

'They are trying to help, Gibbs,' a voice boomed from the landing on the metal stairs. Vance was resting his elbows on the cold banister and staring down at the three agents. 'Media will be all over this when they find out. We need this solved as quickly as possible.' He straightened up and slowly descended the stairs. The crowd parted to let him through and he joined the group of lone agents in the bullpen. The crowd stared at the isolated group, impatient for attention. 'All agencies want this,' Vance told Gibbs quietly, acutely aware of the scrutiny.

'This is our investigation, Leon,' Gibbs stated firmly. 'Fifteen of the deaths were Marines. It is NCIS jurisdiction.'

'No one is disputing that, Gibbs,' Vance reassured the irate special agent. 'But we need to solve this quickly.'

'You already said that,' Tony mentioned with a goofy smirk on his face. He was silenced by stony glares from all agents present. 'Sorry.'

'Was it an international assassination?' Ziva asked, the recollections of her Mossad days returning.

'Possibly,' Vance replied curtly. 'No country has claimed responsibility.'

'It could still be a country with tense political ties to the US,' mused Ziva.

Vance turned to Gibbs. 'Use all the resources offered,' he ordered. 'And be nice to them.' He gestured to the hushed assembly behind him. Gibbs kept Vance's gaze but made no acknowledgement of the command. Vance held the older man's defiant stare for a moment before turning on his heel and returning to his office.

Gibbs watched him leave before turning away from the expectant mob. 'Get McGee,' he instructed.

Ziva spun around and picked up her phone decisively. Rarely did a succession of efficient, professional assassinations involve her anymore and, even when they had been a regular feature of her life, she had always been on the executing end, never investigating the assassin. She was not overwhelmed with the sour memories surfacing but she knew her eyes had floundered earlier and she did not want Tony to misread the signals and decide that she was an emotional wreck. She needed no sympathy because the situation was not affecting her untowardly.

'Abby,' she greeted into the mouthpiece. 'Send McGee back up, please.' She replaced the phone into its cradle and turned back to her colleagues. 'He is on his way up,' she announced, striding over to the pair of senior agents.

'What are the possibilities?' Gibbs asked. 'Political assassination,' he began.

'Serial killer,' Tony cried.

Ziva shook her head. 'It was too clean for a serial killer. They don't kill all in one night. Not without any witnesses.' Tony pulled a face at her. 'Personal kills by a professional assassin,' she continued the list of options. Tony raised his eyebrows unbelievingly. 'They are quite common,' she explained to her partner. 'Retribution for loved ones killed by Marines,' she suggested. 'A trained assassin would not pass up their advantage. They are trained to long for revenge and they would easily be able to pull it off undetected.'

Tony looked at her curiously. 'Sounds like you're talking from experience.'

Ziva ignored him and instead turned to Gibbs. 'That is only two ideas. There are many more.'

'Why are you so sure it is a professional?' Tony inquired.

'Because, Tony, nobody else could engineer such a feat. Whoever did this was trained. You could not kill nineteen people in one night. Fifteen of them were also trained fighters. They would not have been easy targets.' Her voice contained thinly veiled distaste for her partner's ignorance. Tony pulled another face. Gibbs shook his head and turned away from his bickering agents, welcoming the arrival of McGee.

'Get your gear,' he ordered. 'We have a lot of crime scenes to visit.'

Tony stared at him incredulously. 'We don't have to process them all do we, Boss? Didn't Vance say we should catch the killer quickly?'

'Metro are processing the crime scenes. They have more available hands. We, however, still need to visit the scenes in case they miss anything,' Gibbs told him impatiently, striding through the flock of waiting agents.

'Boss, what about them?' McGee shouted after him.

Gibbs surveyed them thoughtfully. 'Talk to the director,' he advised them. 'See if he has any jobs for you.' Some members of the throng shook their heads in disgust at this insult and followed the team into the elevator to leave. Most, however, stayed to wait for further instructions out of fear of their direct orders to help the investigation. A wave of apprehension on behalf of his boss passed over McGee as he navigated his way through to reach the elevator. Vance would not be pleased with the dismissal of willing hands. Gibbs was a political nightmare.

The car journey to the first crime scene was short but seemed like an age to McGee. Gibbs was irritated with the unwelcome visitors and McGee, sitting in the front for the first time in ages, was feeling the anger exuding from his taciturn boss. McGee was also being poked by Tony in the back but was afraid to snap at him for fear of awakening Gibbs's annoyance. McGee fervently wished Ziva would stop acting so hostile to Tony and regain his full attention because when Ziva ignored Tony, Tony turned his focus on the hapless McGee who had less resilience to Tony's habits. So, when Gibbs braked sharply, signally their arrival, McGee fell thankfully out of the car and hurried as far away from his colleagues as possible.

'What do you have?' Gibbs asked the policeman in charge.

'No tyre marks, no footprints, no fingerprints, no hair and no clue as to who did this,' was the unencouraging response. 'No witnesses but neighbours heard one gunshot at quarter past eleven last night.' He paused to gauge Gibbs's reaction, considering how much he was going to include him in the overall federal investigation. Gibbs's face showed no signs of gratitude or compliance to any whims of the police so he continued flatly. 'Bullet went right through the man's skull, entered right between the eyes and exited directly behind. Bullet lodged in the wall behind.'

Gibbs allowed the poor man a small smile before turning on his heel and joining his agents by the body. The Naval Officer lay rigid on his back on the pavement stained with his blood. A half formed look of shock was permanently etched on his face. He had facing his killer directly on but he only knew what was to happen in the final seconds of his hastily ended life. He must have seen his killer approach but was oblivious as to their deadly intent. Gibbs shuddered involuntarily. The action could be reduced to bare simplicity but must have taken meticulous planning, a skilled hand and an emotionless person to execute this man; the first of almost twenty victims in one night, less than six hours.

Ziva scanned the body disinterestedly but her attention was caught by the bullet hole between the victim's eyes. It had streaked cleanly through the skull, killing him instantly. The hole was small and was hardly spattered with blood. The shot had been so precise that the force had no ejected a torrent of blood onto the head. The pool around his head came from the exit wound on the back of his head. Very few people could shoot with the required amount of accuracy to achieve that result. There was no doubt that the killer was one of the best in the world. As she surveyed the wound, a thought ploughed into her soul. Would she be able to do that? She had been on her way to being the best shot in Mossad when she had left Israel for America. Now that she was out of practice, would she ever be able to shoot that well? Somehow she doubted it. She meant what she had said to Liat in the bathroom; she was proud to have been accepted by NCIS, but her desire to be the best was too strongly ingrained in her to let go. The hole seemed to taunt her and her mind was suddenly overridden with gunshots and screams, the howl of death served by her and her gun. She blinked hard and the haunting cries stopped but her heart continued to pound. She didn't regret any kills – not even Ari – but she never dwelt on her actions. Maybe if she spent some time analysing them she would feel differently. In Mossad, she never allowed herself time to reflect on her duties but NCIS kept a slower pace. Ziva frowned. She didn't know where these profound thoughts had suddenly come from. She shook them off and dragged her eyes off the neat, fatal, mesmerising hole.

It ran away with me a bit – please tell me if it is waffling too much. Is it good enough to continue? I'm not sure.