A/N Thanks to y wonderful beta and remember this is an AU so timelines may not follow the exact same way.

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"Sergei?" Ziva whispered it had been a long time since she'd seen Ari's half-brother. They had a unique family tree.

"I came to apologise Ziva."

"About what?" She frowned at him, what on earth he could need to say sorry about.

"You are injured because of me. I am so full of anger. I never even thought about you being a part of NCIS." He took a deep breath. "I want to get revenge on those who killed our brother."

Ziva easily kept any emotions of her face, after all the death of Ari was at her hands. The director of Mossad had made that order, and just like a good soldier and daughter, she followed through. Sergei's feelings were something that she understood revenge was something that needed to be dished out when required. That was when it hit her, Sergei could get his revenge, or think he did and Ziva could get hers.

"You have done nothing that needs forgiveness from me. We both want him to be avenged. I've tried, but I am too close and would be a suspect. He is also a coward who runs at the first opportunity."

"Who is this man you speak off?" Sergei demanded.

"The man who murdered our beloved brother in cold blood is Anthony DiNozzo Jr."

"There is no evidence that this person was involved."

"Of course there isn't, the information had 'disappeared.' He is, after all, Gibbs' favourite." Ziva spat out the words, she is more important than him and should be treated like so. "The Director helped, no one would go against those two men, and they are both highly respected. But like the weak man he is, Tony allowed them to do this."

"How did you find out about this?" He observed her intently, things seemed a little off, but why would Ziva lie? She wouldn't protect the killer, would she?

"My teammate and friend Timothy McGee, he knew how upset I was over the cold-blooded murder of Ari. He looked into it for me; his skills are very impressive when it comes to computers. Some files had been missed, and it explained what had truly happened. Tony came and shot him in the back; there was no reason why that I can see. Gibbs and Ari seemed just to be having a civilised conversation. One of Mossad's enemies may have hired him. He does have very expensive tastes."

XXXXX

McGee glanced up as Ziva sat down. "How are you feeling?"

"Better, thank you, McGee." She glanced around and noticed that they were alone. "Where is Gibbs?"

"He and Tony went back to the warehouse." He froze suddenly remembering that Gibbs told him not to say anything.

"Alone, without backup?"

"They have each other; we've all gone out in pairs before." He had no idea why Ziva wasn't allowed to know; they were teammates after all.

She grabbed her cell and typed a message to Sergei letting him know where DiNozzo was. Ziva looked up and noticed his questioning look. "A neighbour was worried about me. I was just letting her know I was released from the hospital."

"I'm glad you have friends outside of work."

"As am I McGee."

XXXXX

Gibbs knelt down to look at fragments of what could be part of the bomb. Something felt off and then he heard the sound of feet breaking twigs. He stood, turned with his gun in hand and fired. Tony's body hit the ground with a thud.

"DiNozzo?" He called out, panic in his voice. His eyes never left the shooter who was also still on the ground as he reached out to check for a pulse. He sighed with relief as he felt one.

Slowly he stood and made his way over to the other body. Gibbs grabbed the gun and then checked for a pulse on him. There was one; hopefully, that meant they could find out what the hell was going on. He pulled out his cell and called for ambulances and then to Vance to update him. Were they watching or did they have a spy within NCIS?

XXXXX

Gibbs sat with Tony until the doctor finally kicked him out. It still bothered him how someone knew they were there. He headed to Balboa who was in charge of the prisoner, so there wouldn't be any conflict. They needed answers; he had to make sure that Tony was going to be safe, so it had to end.

"How's Tony?" Balboa asked as soon as Gibbs walked in.

"The doctor's with him now."

"Hopefully, he'll be okay."

"The coward should die for what he has done." A voice growled from the hospital bed.

"Who are you?" Gibbs needed to know who this man was.

"Sergei Mishnev."

It meant nothing to either of the agents.

"What exactly do you think he's done?" .

"You know what happened; you helped cover it up."

Balboa looked for clarification, and Gibbs just shrugged his shoulders. He had no idea what the hell was going on.

"Maybe you could tell me if there was a cover-up, it's something I should know." Balboa cajoled.

"He killed my brother." Sergei looked at the two men if this was known maybe more of those involved could be taken down. He had nothing to lose in passing information on.

"And your brother is?" Gibbs demanded.

"You don't even remember his name. You were there when your agent shot him in the back, in your home."

"Wait, are you talking about Ari?" He needed to clarify things first.

"Yes, my beloved half-brother."

Balboa looked confused about what the hell was going on.

"DiNozzo didn't kill Ari. He wasn't even there; I don't know who told you that he was."

"You would say that."

"Who told you..?" It suddenly made sense, McGee must have told Ziva where they had gone and then she passed it on. "Ziva told you didn't she?"

"She wanted revenge, just as I did."

Gibbs sighed. "She wants revenge all right, but it had nothing to do with Ari. Ziva was the one that killed your half-brother."

"I don't believe you." Sergei spat out, but then the anger faded from his face. All those doubts from the conversation he had with her came flooding back. The reason things felt off was because she had lied to him. "I…"

"What is it?" Balboa could see he'd thought of something.

"I had a conversation with Eli; we talked on and off, mainly passing information. He seemed troubled, and when I asked what was wrong, he told me that he needed to make a great sacrifice. Mossad needed someone on the inside. It was not long after this that Ari was murdered." Ziva had betrayed him, used him for her own reasons.

Gibbs just stared at him. He felt sick to the stomach. Ziva had killed a family member on orders from her father. All to get into NCIS, it had nothing to do with saving him. It was to gain his trust. Everyone knew what kind of man he was and if he trusted her, others would. "Ziva wanted revenge. DiNozzo killed Michael Rivkin; he attacked first. My agent defended himself. She never forgave him for killing the man she loved."

"I thought they had separated." Sergei glanced at the two men. "He was seeing someone else."

"Eli." Gibbs supplied. "How did you find out?"

"I caught them in a compromising position once. Eli wanted me to understand how they loved each other. They were going to tell Ziva about their feelings. He was sure that being his daughter that she would forgive them. But then Michael died and finally Eli passed from this world."

Balboa managed to keep the surprise off his face. He'd never been involved in such a soap opera type case.

"When DiNozzo arrived Rivkin seemed to be drunk. We think he planned on telling her that night. He died before he could do that. Ziva still thinks that he loved her and wanted to spend his life with her."

"If she had only told me about Ari, I would've understood there was no reason to lie. I understand duty."

"She didn't do it to spare your feelings. Ziva made that story up to use you. If you killed DiNozzo, her revenge was complete and Ari's death was the reason you did it." He ran a hand through his short silver hair.

"It would be okay with her if I was arrested or died." Sergei now understood how she'd played him. It was evident nothing matter to Ziva apart from her own wants and needs. He could still get his revenge on her and for Ari all in one swoop.

"Yes it would've been she doesn't care about anyone else. Ziva is only in things for herself." Gibbs was still angry at himself for how he was played. DiNozzo nearly died because of his stupidity.

Sergei looked over at them. "How can I help?"

"A full confession and agree to be a witness against Ziva. We'll see what we can do to help you."

"I doubt there is much you can do; there are many crimes in my past that will come forward. I have one condition."

"What's the condition?" Balboa asked.

Sergei smiled. "I want to be the one to tell Ziva about her father and Michael."

Gibbs chuckled. "I think we can arrange that."

He knew he would face prison in this or another country, which was if he arrived there alive. Sergei had many enemies that would love to see him dead and some of those were men in power.

XXXXX

Gibbs and Balboa stood outside Sergei's room.

"We need to have guards in and outside. His name can't be anywhere. McGee can't know and Ziva isn't allowed to catch a glimpse of him. Balboa you pick agents you trust and put them on radio silence. Nothing gets back to anyone until we want them to."

"I know just the agents."

"I'm going to check on Tony and then see Vance. He needs to know what's going on and to approve it."

"I'll start to organise things."

"As soon as I get the go ahead I'll let you know."

XXXXX

"How's Tony?" Vance asked immediately.

"He's okay; it's a through and through. Tony hit his head hard when he landed on the ground, which was what knocked him out."

"Do we know what happened?"

"Ziva." He watched as Vance sighed.

"Tell me everything."

"She told Ari's half-brother that Tony killed him and we covered it up."

"He believed you when you explained what she did."

"Sergei had a conversation with Eli before Ziva joined us. He was told that a huge sacrifice was needed to get Mossad inside."

"Wait, Ziva killed her half-brother, ordered by her father to get her a position here. To earn our trust." The Director looked disgusted that a family would do that.

"He's willing to do anything to take Ziva down after he found how she used him. He does have one condition."

"Which is?"

"He wants to be the one to tell Ziva about her boyfriend and her father."

"I think we can manage that, as long as there is enough security."

"I thought you might. I've got Balboa setting things up. I do have a plan on how we can set them up."

"Walk me through this plan before I agree to anything."

XXXXX

Gibbs rubbed his forehead as he joined his team.

"Are you okay boss?"

"Where's Tony?" Ziva hoped things had worked out the way she planned.

"He's confirming some statements."

Her face fell at the fact her plan had failed.

"Statements from whom?" She had to know what happened to Sergei and if she had to deal with him.

"We were attacked at the warehouse; Tony was quicker but…"

"But what?" Ziva demanded.

TBC