Title: When Two Worlds Collide
Rating: PG-13
Category: Case fic
Genre: Gen
Pairing: None currently
Summary: Gibbs is due to retire but first he has to get through one last case.
Disclaimer: The characters herein belong to DPB, CBS, Paramount, et al. No copyright infringement is intended.

He turned towards the source of the familiar voice, flipping his phone closed as his eyes came to rest on the figure standing on front of the elevator, "Ziva?" he questioned, the voice was familiar to him but the woman dressed in a dark suit and stilettos did not match his memories of the agent who had returned to Israel following her father's death.

"Don't let the outfit fool you; I could still murder you in ten different ways with a paperclip…" A smile crossed her face and she quickly closed the gap between them wrapping her arms around him as he pulled her into a hug, pulling back she looked at him closely, "Jethro you have not changed one bit… I have missed you…"

"I missed you too Ziva… What are you doing here?"

She moved to her old desk, pulling out the chair and sitting down. Looking up at him she answered his question, "The fact NCIS has run Shai's DNA through our database was brought to my attention. I boarded a plane straightaway and flew overnight to Washington. Shai was working here at my personal request."

Gibbs looked towards he puzzled, "If Officer Levi was here at your personal request why was I informed only the director was authorised to reveal the details of his mission?"

"Jethro I am the Director of Mossad… following my father's death the Prime Minister stated he wished for Mossad to appear more accessible to the people of Israel. He wanted the public to know that we are an intelligence service dedicated to protecting not just our own nation but also those of our allies; we are not a secret society of assassins. Upon my return I was appointed my father's successor, it was hoped that the senior members respect for my father would enable me to do the job whilst moving the agency in the direction the Prime Minister wished. But that is not important, what is important is the reason Shai was in Washington in the first place. My father maybe dead, and whilst outwardly all those in the agency have shown themselves to be loyal to me and the new direction there are still those within the service who remain loyal to him; those who are prepared to exact revenge on his behalf and restore honour to me family. Those who believe Ari was a valuable mole within Hamas and not a traitor to my family and my country; those who believe you murdered him. Jethro they can do nothing about me and the fact I brought dishonour upon my father by working for the man believed to be responsible for Ari's death, but you… they still believe that killing you will restore the honour of my father."

"Are you saying Officer Levi was in this country to murder me?"

Her eyes flashed up to meet his, "No! Of course not, I told you he was here at my personal request. It was brought to my attention that several of my father's closest allies had been meeting secretly. I looked into it and I believe they were planning on sending another agent who remained loyal to the old ways to America to kill you. Shai was here to protect you. He was instructed to find the officer in question and neutralise him."

"Are you telling me you authorised an assassination on American soil?"

She looked up at him, her face devoid of any emotion, "I simply instructed Officer Levi to use any force he felt to be necessary. The man in question was a disgrace to Mossad and a liability to my country; should he have succeeded in killing you the trust between our two nations would have been severely compromised." She rose from her chair, "I must speak with Director Vance..."

She walked past him and headed up the stairs, he watched speechless as she disappeared into the director's office, only come out of his trance as he heard the elevator doors ping and slide open, "Morning boss!"

He turned to see McGee walk out into the bullpen closely followed by Jen and Moretti, they all quickly crossed to their desks, both men sat down and began to work but Jen paused, "Someone's been at my desk since I left…"

Gibbs peered at her over the rim of his glasses, "Yes, is that a problem?"

"No, no of course not… I was just wondering if you knew who it was…"

"Yes I do."

She sighed sliding into her seat, "But you're not going to tell me…"

"Ziva…" McGee's voice cut across the conversation, the incredulity clear in it.

Jen looked at him puzzled, "The officer I replaced? I thought she was in Israel…"

Gibbs snapped at her, "Officer David was one of a kind, you did not replace her. She is irreplaceable."

"It is Ziva…" McGee's voice came again clearly oblivious to the minor disagreement that had just taken place. This time all three pairs of eyes followed in the direction McGee was looking in and came to rest on the two figures standing at the top of the stairs looking down at them. The bullpen went silent as the pair made their way down to join them. Director Vance was the first to speak as they reached them, "Special Agent Gibbs, Director David has just informed me of the possible situation surrounding you and this case. Whilst I firmly believe you should be placed in protective custody for your own safety she seems to disagree."

Ziva cut in, "Protective custody would leave him an easy target. Mossad officers are trained to do exactly this sort of thing; you could surround him with four, five even ten of your agents and as long as you confine him to one place you are almost certainly signing his death warrant. Plus this is Gibbs we are talking about; he would give them the slip at the first available opportunity."

"I'm sitting right here you know…" Ziva turned to the source of the noise, seeming to register the fact that he was there for the first time since her return from the Director's office., "Of course, sorry Gibbs…"

McGee looked between the pair of them and then back to the other two members of the team, "Hey boss, Ziva could one of you let us in on the secret. What does out case have to do with you and protective custody?"

Ziva turned to him opening her mouth to answer as the elevator doors pinged once more and another familiar voice filled the room, "So the new director of Mossad can't control her own house… That's not good Zee-vah; I'm not always going to be here to clear up your messes…"