Disclaimer: NCIS and its characters do not belong to me and I am making no money from this.

Many thanks to Mr VP for the Beta. Any remaining mistakes are mine.

AN: Thank you so much for the reviews, they are really encouraging to receive.

The seemingly endless whirl of military transport was exhausting. Plane to the Enterprise, helo to boat to which they were lowered by rope from the transport helicopter along with a contingent of engineers and on to the stricken submarine. In all the trip took a little over five hours during which time Gibbs caught several catnaps and DiNozzo slept not at all. Glaring at the ex-marine Tony envied his boss his ability to sleep almost anywhere. He had always found it hard to sleep on a plane and travelling on water made sleep all but impossible as far as he was concerned. Now, waiting his turn to climb the side of the Surreptitious he took a good look around. There was a slow swell bringing the boat together with the side of the sub and the clouds on the horizon heralded rain. The sun was low in the sky and would soon disappear behind the bank of cloud, setting early. Most worryingly the Surreptitious herself was listing to port as a result of the damage from the explosion. Tony grimaced, not looking forward to being on board during the coming storm.

"Hey DiNozzo, you coming?" Gibbs' voice startled him from his thoughts and, with a last look around he quickly scaled the conning tower ladder and climbed on board. Gibbs was already talking to the captain but once glance at his face told Tony all he needed to know. Nothing new from DC. He grimaced, he wouldn't want to be in McGee or Ziva's shoes right now, but Ducky should have finished the autopsy and Abby surely would have something by now. Revising his thoughts slightly he joined Gibbs and the captain just in time to hear the end of the captain's explanation.

"I'm sorry Agent Gibbs, there is just no way to get through right now."

DiNozzo noted the slight shift in Gibbs' eyes and, taking the hint, stayed silent. Gibbs nodded to him and introduced the two men briefly. "Captain Root, Special Agent DiNozzo."

"Captain," Tony nodded at the officer, stepping aside to let the team of engineers precede him down the hatch. The explosion had occurred aft of the engine room damaging one of the starboard ballast tanks and flooding two compartments. The chief engineer and two of his staff had been lost and were yet to be retrieved. The engineering team that had accompanied them hoped to make running repairs so that they could make their way to rendezvous with the two American destroyers who were heading their way.

Casting a last look around Tony followed Gibbs down the conning tower ladder. He was immediately assaulted by the noise and smells of a submarine. He knew from experience that they would soon fade into the background but for now the smell of oil was almost overpowering. Despite the tang he liked submarines, had always felt comfortable on board. Something was nagging at him now though and he'd worked for Gibbs long enough to know that you didn't ignore feelings like that.

The engineers had already moved forward by the time Tony set foot in the control room. He joined Gibbs and Captain Root around the chart table for a briefing.

"Why has radio contact been lost captain? Gibbs asked quietly. "Your mayday got through."

Root looked at him assessingly before saying abruptly. "Come to my cabin, we can talk there."

Gibbs looked briefly at DiNozzo, raising his eyebrows minutely before they both followed the other man without a word. Root led them into a tiny space, just big enough for a bunk and a compact desk, situated just aft of the control room. He gestured to the bunk and both agents sat down whilst Root took the only chair.

"Our communications have been sabotaged," he began quietly once the door was closed. "I haven't broadcast it, this is a young crew and I don't want panic but it looks like acid of some sort has been introduced into the circuitry. We were able to get off a mayday because it hadn't fully eaten through the cabling. It's a write off now. I instructed the launch that brought you to stand to, they can act as courier but their equipment doesn't have the range that ours did."

Gibbs pulled a face as he considered the options. "How long before the launch could rendezvous with the nearest destroyer?" he asked.

Root shrugged. "Last we heard she was nine hours from our position, that was four hours ago, communications were patchy then."

"They put it down to the storm front," Gibbs said. "Still had a fix on you though." He looked thoughtfully at DiNozzo who sat quietly beside him. "Where is your GPS transponder Captain?"

"In the control room," the captain replied thoughtfully, reaching for a wall mounted intercom panel. Calmly he ordered the COB to report to his cabin, remaining silent until the man arrived a few moments later. "Chief, I want you to place a guard over our GPS transponder," he ordered quietly.

"Aye Sir," the chief replied with calm efficiency before turning and leaving the tiny cabin. He had barely left the room when an explosion rocked the hull.

"What the hell?" Root echoed the thoughts of the NCIS agents as all three men shot to their feet and made for the control room.

"Report," Root demanded.

Gibbs, on his heels, was impressed at the calm efficiency on show, though he was conscious of the undercurrent of tension.

"The launch just blew up Captain," the XO reported, nodding towards the damage control teams making their way on deck.

"Damage?"

The XO shook his head. "She's gone Sir," he said quietly, "I've got spotters looking for men in the water. We've sprung a few loose plates but are not taking on water."

DiNozzo looked helplessly over at Gibbs seeing the fury he felt reflected in the older man's eyes. Clearly the saboteur was still on board and had struck again. They needed to determine his agenda sooner rather than later. Time to find out how Stevenson fit into things.

"Is there somewhere we can set up Sir?" Gibbs asked quietly. "We need to speak to Lieutenant Stevenson"

Root looked at him assessingly for a moment before calling the COB over and directing him to show the NCIS agents to the wardroom to wait for Stevenson.

"Thank you Sir," Gibbs began but the CO had already turned back to supervise the recovery operation.

Minutes later they sat on two sides of the small table in the wardroom waiting for Stevenson. DiNozzo had set up his laptop and brought up Stevenson's service record. On the surface it was exemplary but Tony had dug a little deeper before leaving the office and there were several informal complaints against the man. As yet they didn't know why they hadn't made it to his records.

Tony looked up at the tap on the doorframe. His son had looked a lot like him. He glanced across at Gibbs and waited for him to being the questioning. They had decided, by tacit agreement to talk to him first before breaking the news of his son's death. Sometimes it was necessary to be devious and Gibbs, straight talker that he was, was a master.

"Sit down Lieutenant," Gibbs gestured to the seat at the end of the small table. Stevenson, who was well over six foot, curled himself into the chair, his head to one side in what, Gibbs supposed, was a permanent state whilst working within the cramped confines of the submarine.

Gibbs pulled the file across the table so that it sat in front of him and looked steadily at the other man for a moment. Stevenson was unable to maintain eye contact and his gaze flicked across to DiNozzo who pretended interest in his laptop, not even raising his eyes. The silence stretched out, comfortably enough for the NCIS agents but not so for Stevenson. He tried to maintain an outward air of calm but beads of sweat appeared on his forehead and, listening carefully, DiNozzo could hear a slight hitch in the man's breathing. Barely a minute had passed before he looked up briefly at Gibbs and asked shakily. "Why am I here Sir?"

Gibbs didn't break his stare. "Why do you think Lieutenant? Surreptitious is dead in the water, the launch was just destroyed."

"You can't think that was me Sir," Stevenson protested wildly.

"Why not?" Gibbs asked mildly. "Give me a good reason"

DiNozzo smiled to himself as he watched the man play into Gibbs' hands.

"You can ask anyone, I never left my post."

"Never?" Gibbs continued, voice deceptively mild. "Not once during the past twenty four hours? You didn't go to the head? You were supervising the lines when we arrived, I saw you on the casing. You would have had plenty of opportunity to get near the launch."

"But I didn't Sir, I didn't leave the casing at all."

Tony looked up at the ring of truth in his words. Stevenson had relaxed somewhat too, so, he wasn't working alone DiNozzo reasoned. There was no doubt in his mind that the man was hiding something but equally obviously it hadn't been him that had blown up the launch.

Gibbs changed tack having reached the same conclusions as DiNozzo. He looked down at the folder in his hands. "There have been several complaints made against you Lieutenant," he began.

"None of which have ever been upheld Sir."

Gibbs smiled and looked carefully at him as he replied. "Your father is Rear Admiral in Norfolk I believe"

And there it was, the flash of resentment crossed his face before he could hide it and Tony knew that it wouldn't be long now before Gibbs had the truth.

Stevenson said nothing but his sullen silence spoke volumes. Gibbs looked at him for a moment and then simply asked, "Why?"

Stevenson seemed smaller when he spoke but his voice still held a note of defiance. "Because I mattered, I could actually make a difference and someone gave a damn."

Tony looked up sharply hearing the echo of past conversations with his father but he knew he could never have made the choice the other man had. Gibbs knew it too for he turned his head instinctively to look Tony in the eye for a moment, a slight smile on his face, before turning back and asking. "Who approached you, what did you have to do?"

Five minutes later both agents were reeling at the stupidity of the other man. He had betrayed his country, his shipmates all because of feelings of resentment towards his father and to someone whom he had never even seen. His contact had been at Norfolk and, unfortunately, Gibbs believed him when he said that he didn't know of another operative on board.

"Did they pay you?" Gibbs asked finally.

"No Sir," Stevenson's head came up in a faint echo of his precious defiance before his voice dropped to a whisper. "No Sir, I did it at first to get back at my old man, nothing big but then they held it over me and I couldn't get out."

"You didn't want to."

"I tried Sir, when it came to Surreptitious I did try but they," he swallowed, unable to go on.

"They threatened your son," Gibbs supplied, his face grim.

"How did…" Stevenson began before looking up into Gibbs' eyes, his face crumpling as he realised the truth.

TBC