I know some of you are frustrated because there are a lot of... how do you say it... loose ends (I think?) There are a lot of question marks and you have to be patient to find out what happens. In this chapter you will find out what has happened to TONY, so it should calm your curiosity to a certain extent.
As for the question: who is the mysterious man? You will have to be a bit more patient for that one, you'll find out in a few chapters. I am leaving you bread crumbs though, so that you prepare yourself to discover the mysterious identity... enjoy your reading and thanks for the reviews! :)

"What? Aren't you glad to see me?"
"You…"
Tony reached for his gun he had just laid on top of the cupboard, but the man in front of him pointed a gun to his head as soon as he was about to move.
"See, I wouldn't do that if I were you. Give me your gun. And your knife."
"I don't have a knife." Tony lied.
He had always been an honest man, so he wasn't really a good liar. As Wendy once said "Tony is the most honest person I know. The only person he doesn't seem to be able to be honest with is himself". On top of that, the man who was standing in his kitchen knew for certain he had one.
"DiNozzo, come on. You used to be a better liar than that."
Tony found out it was pointless to argue, so he threw his gun and knife on the floor.
"Good."
"What do you want? You're supposed to be dead…"
"Right! I'm dead! Only you see, I have died many many times already, and it seems I always manage to survive somehow. Your bad."
"What do you want." Tony said it slowly and made a pause between every word. He wanted this to be over.
"I want you to go to your office and get me something."
"And if I don't?"
The man walked towards him, still holding the gun in his hand.
"Let me get this straight for you now. You hadn't a clue I was alive for the past few years but I have followed your every move. I know what you did back in Somalia, pretty heroic and a little cheesy if I may say. The point is, I know you're not afraid to die, DiNozzo. I also know it would be a real shame if something were to happen to Ziva…"
"Are you threatening Ziva now?"
The man stood silent.
"What is it you want me to get?" Tony was giving in. He couldn't take a stand when Ziva's life was at stake. He knew how dangerous this man was, he couldn't risk losing her again.
"I want you to get something from Ziva's desk for me. It's a flash drive, it is in her bottom left hand drawer, in a small red box."
"Why do you want the flash drive?"
"This I cannot tell you. I can only tell you that if the information in contains were to be diffused, I would immediately have to kill Ziva. You have 24 hours to deliver me the flash-drive here at your apartment. If you don't you know what happens to the Israeli beauty…"
The man then looked down at the gun, which was now only a few inches away from Tony's chest.
"I am so sorry, I had almost forgotten how to be a gentleman, just like old days."

He threw his gun on the ground. Tony thought he saw a chance to stop the crazy man he had in front of him. He came to him and tried to hit him with a box of cigars he had managed to grab. Not that he smoked cigars, of course, but he always thought they were tremendously classy. Only, Tony forgot how fast this man was, and he didn't notice he had a long sharp knife hidden behind his back. Everything happened extremely quickly. Tony didn't almost feel the blade slide between his lower rib and behing his ribcage, through his stomach and perforating slightly his right lung. The man threw him a punch across the face. Tony stumbled and fell on his knees, panting, holding his side.

"See? You shouldn't have done that. Don't be a pussy, I didn't touch any arteries, you're not going bleed out. However, this might get serious in an hour. You have an hour time to go to your office, find the key and bring it back here. Isn't that wonderful? I even might see you die, slowly and painfully if you manage to make it back."
Tony didn't answer; he had to catch his breath both from the punch and from the wound. The man knelt next to him and whispered into his ear:
"I suggest you get going, you haven't got much time ahead of you. It looks like a nasty scratch you got down there. The deal still stands, don't let anyone know I was here and bring me the key in 24H tops. Otherwise she dies. I'll make it as painful as for you."

The man walked out of the apartment. Tony grabbed the edge of the table and somehow managed to stand up. He had trouble breathing but he could walk. Of course he had to help himself with something. He had no time to lose. He got to his car as fast as he could, but he was starting to breathe really heavily. He drove to the Navy Yard as fast as he could. He gave a quick glance to the clock of his car: 3.36 p.m.

He double parked his car right in front of the entrance. He could barely step out of the car, it was of no use parking it. He slowly held on to the wall to help him walk into the NCIS HQ. He didn't have time to wonder why nobody was guarding it. He pressed the elevator button. He felt his legs shaking. He didn't have much time before collapsing. The elevator mercifully dinged, and Tony threw himself inside. He pressed the second floor button, and held on to the sides of the elevator. He couldn't hold on for much longer. His breath was getting heavier and heavier, as if someone was strangling his lungs. The elevator doors opened. Yes, he could do it. He still had enough strength to get there. He tried to walk out of the elevator, and he almost fell down. His legs weren't able to hold his weight anymore. He fell on the desk right in front of the elevator. "I can't do this, I can't". But then a voice inside him told him "Dammit Tony, he's going to kill Ziva!". This gave him back a strength he didn't know how he could possibly still have inside him. He walked a few steps. The mind over the body doesn't always work, and Tony fell on his knees, gasping for air. "I have to get there" he kept telling himself. But a few seconds later, even his knees wouldn't work anymore. His hand slipped and he fell on his chest, feeling something crack inside, probably a rib already damaged by the blade. He started crawling desperately towards the desk. "I'm doing it for her, for my Ziva" he kept saying that to himself. Suddenly, he could no longer breathe. He started coughing loudly, spitting his own blood. He couldn't. He laid down.

Right when he was about to turn unconscious, he felt a lacerating pain to his wound. He opened his eyes. Tony saw the most exquisite vision he could have while dying: Ziva's face. He wanted to yell to her to run like hell, he wanted to hug her and send her away at the same time. But most of all, he was glad she was there. She was talking but he couldn't quite make out what she was saying. It didn't matter. Her voice filled his ears like the one of an angel. "It's a wonderful way to die", Tony thought to himself. He wanted to tell her, to thank her, to tell her she was the best thing that had ever walked into his life. However, Tony could barely breathe. He tried to yell at her "Ziva!", but he realized he could only barely whisper, and it already was too much for him. "You have an hour, my ass!" he thought.
"I'm sorry." he muttered.
And he truly was sorry. If he couldn't provide the man with the flash drive, he was going to come for her, and Tony was already feeling guilty for whatever would have happened to her because he couldn't make it. Because he had been too weak to make it.
He just saw Ziva's face turn pale, then everything turned black, he had stopped breathing, he couldn't breathe anymore. And while blood, fatigue and pain had the best of him, Tony had a smile on his face thinking of the last sight he had: a beautiful Israeli angel, with huge brown eyes filled with tears looking right into his.