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. I have just finished the penultimate chapter so I think I can let you have this one now.

They left Stevenson under guard in the wardroom. The man remained sat at the table a shadow of his former self. Gibbs went to report to the captain and sent DiNozzo aft to talk to the men, to see if he could get a feeling as to who the real saboteur was. It was obvious to Gibbs that Stevenson had been a minor player but he couldn't see him as someone who would have killed in cold blood, whatever the cause. No, there was at least one man aboard who was playing for much higher stakes.

Moments later he reached the control room and looked around the crowded space carefully. The atmosphere was tense, each man concentrating intently on the controls before him. Root stood calmly talking to his XO over the intercom and held up a hand when he saw Gibbs, asking him to wait.

"Captain?" Gibbs asked as Root broke the connection.

"Six bodies recovered from the water," Root spoke quietly for Gibbs' ears only. "No survivors."

Gibbs' mouth tightened. "What's the latest on the storm?"

"Approaching fast, we'll need to close up within a half hour." As he spoke the captain's eyes roved with practised ease over his domain before coming to rest on a monitor just as a piercing alarm sounded.

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DiNozzo made his way aft as quickly as he could but his path was interrupted several times as crewmen hurried past him intent on carrying out the repairs before the storm hit. Being able to submerge to ride it out was definitely a priority. There was an air of unease though which became more prevalent as Tony approached the engine room hatch. It was still sealed but engineers were getting ready to crack it. DiNozzo stood quietly to one side observing the crew. The engineers had all been vetted but, as far as he could tell, all of the crew members seemed completely focused on their task.

"Has the engine room been pumped out?" he asked the crewman who stood next to him.

"Yes Sir," the youngster, who couldn't have been more than nineteen, replied sombrely. "Your engineers have been able to put a patch onto the external plating." He licked dry lips quickly before hurrying forward to assist the engineers in breaking the seal.

The hatch was lifted slowly, no one being keen to be the first to see the horrors awaiting them. Such was the tension that everyone in the small area jumped when the hatch abruptly crashed to the deck. Recovering quickly DiNozzo's eyes were drawn to the small object that suddenly flew from the open hatch. He recognised it instantly but by then it was already too late. "Get down," he yelled, throwing himself towards the young seaman even as the percussive force of the stun grenade threw him to the deck. His hold on consciousness slipping rapidly he just made out a shadowy figure emerging from the open hatchway before his eyes slid closed.

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"What the …..," Root muttered as he signalled for the alarm to be silenced. "Damage control teams aft" he ordered. "Fire," he said succinctly at Gibbs' look.

Gibbs blanched, he had sent DiNozzo aft. With one last glance around the control room he took off after the damage control teams, being careful to stay out of their way. Moments later they reached a sealed compartment.

"Damage control," the DC rating keyed the intercom and announced their arrival, even as he tried to open the compartment. All of the damage control team were wearing breathing apparatus and Gibbs watched as the officer in charge checked the readouts on a panel.

"No fire," he reported, "high levels of smoke but it is being successfully expelled."

Gibbs and the XO who had accompanied him both nodded, relieved, but Gibbs' gut tightened as he realised that the hatchway to the next compartment remained obdurately sealed. With a sinking feeling he realised that they no longer needed to look for the saboteurs. The saboteurs had come to them.

"Can we get a visual of the next compartment?" he asked the XO.

"Sorry Sir, no can do, we can get readouts of O2 levels, temperature and so on but there are no cameras installed."

"Is there access from the other side?"

The XO shook his head. "Not from here. The forward torpedo room is the last compartment in the boat and is beyond this one. This is where your engineers were working to gain access to the engine room on the lower deck."

Gibbs closed his eyes for a moment trying to visualise the layout. "Blueprints? he asked succinctly.

"In the control room."

"Captain," Gibbs drew Root aside as soon as he reached the control room. "What can you tell me about your chief engineer?"

"He's dead," Root replied incredulously. "He drowned when the engine room flooded."

"Are you sure that it flooded?" Gibbs persisted. "Would it be possible to fake the readings up here in the control room?"

Root was about to protest but years of training took over and he tilted his head to the side as he considered the possibilities. "I suppose it could be done," he mused slowly. "But not many people would know how. It would be complicated, not just altering one reading. The trim, the ballast….."

"But a chief engineer could have done it?" Gibbs interrupted.

Root didn't reply but the look on his face told Gibbs all he needed to know.

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DiNozzo woke gradually, every muscle sore, whether from the effects of the stun grenade, of hitting the deck or simply his exhaustion he neither knew nor cared. He looked around slowly from where he lay, instinctively keeping still until he knew what he was facing. He was half on top of the young seaman he had tried to warn and could see two more bodies to his right. Listening carefully he could hear a quiet coughing from behind him and a soft hiss to his right but out of his field of vision. Telling himself to focus he tried to identify the sound, breathing gently through his nose so as not to cough. Coughing, that was it, breathing apparatus. Cursing his sluggish mind he rejoiced in the small victory. Obviously whoever threw the stun grenade wouldn't want to get caught in it themselves so, breathing apparatus.

He listened again, trying to decide if he could hear a second hiss when a sudden bang caught his attention and he twitched involuntarily. A heavy kick to the gut brought him fully awake and he rolled off the seaman with a groan.

"Nice of you to join us," the voice was masked by the breathing apparatus but was clear enough to understand easily. "Looks like your friends want to join us."

Tony closed his eyes then opened them fully, easing himself into a sitting position, one hand clutching his stomach. "Friends?" he queried, coughing to hide his disgust at asking such a stupid question.

The figure nodded its head towards the hatchway behind where it stood. As if on cue a hammering began again as the crew tried to break down the hatch.

Tony noticed the metal bar wedged across the opening, effectively sealing the compartment from the inside. He carefully took stock; besides himself there were two engineers, both coming to and three ratings, one of whom was still out cold. They were being 'supervised' by two men in breathing apparatus, both armed with combat knives. So at least two saboteurs other than Stevenson, he reasoned and six hostages. Not insurmountable odds, unless there were more below in the engine room. He tried to remember how many had been reported drowned but his sluggish thoughts refused to cooperate. Blinking rapidly he shook his head and then immediately regretted it as millions of tiny daggers erupted in his head, breathing deeply he tried again, opening his eyes slowly and focusing on the problem at hand. Hostage situation, get the captors talking. Knowing that Gibbs would want as much information as he could pass on he eased himself upright against the bulkhead and studied their captors. Going by his body language and the fact that he was the only one to have spoken so far the man in front of him was in charge. Yet Tony still had the niggling feeling that there was at least one person left in the engine room and gut instinct was never to be ignored. Sighing he settled back for a long wait.

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"The storm front is almost on us Sir," the lookout reporting from the bridge brought Gibbs' head up from where he was studying the blueprints in the chart room.

"Clear the bridge," Root ordered calmly. "Rig for heavy seas."

Gibbs grimaced, without power Surreptitious would be at the mercy of the weather, severe rolling would hinder any rescue attempts making an external approach via the torpedo room hatch all but impossible. Damn, he had hoped for a little more time. Closing his eyes he visualised the plans of the aft decks, making sure he had them committed to memory. He didn't want any more surprises.

"What can you tell me about your chief engineer Captain?" Gibbs asked quietly.

"Will Michaels, thirty six, been a submariner since he qualified, says he loves the life."

"Family?"

"Not married," Root paused. "Come to think of it I can't ever remember him talking about them. Born and brought up in Maine but he doesn't talk about that either."

Gibbs frowned, wishing he had contact with the rest of his team. McGee would soon be able to ferret out more details, probably already was. He had trained them well and knew that they would be seeking answers from their end whilst he and DiNozzo carried out the on board investigation.

DiNozzo, he frowned again, hoping that the younger man was unharmed. It looked as though they were going to be relying heavily on his instincts to get through this. Lucky he was so resourceful.

"I'm going aft," he said abruptly.

"Hostage situation?" Root queried.

"Looks that way," Gibbs nodded as he left the compartment.

Arriving at the sealed hatch moments later he looked questioningly at the XO. "Any contact?"

"Not yet Sir." The XO balanced lightly on the balls of his feet as Surreptitious dipped suddenly before righting herself. "Can't work outside in this Sir," he added, confirming Gibbs' earlier thoughts. "I wonder what they have planned?"

"Let's find out shall we," Gibbs replied, keying the intercom.

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Tony looked up as the intercom crackled to life. Their captors had been quiet for the past several minutes and he had the feeling they were waiting for something. Or someone. There had been no contact with the engine room but he just knew that there was still someone alive down there.

He looked around the small compartment, everyone was now awake but, despite the fact that the air was now clear, both of their captors still wore breathing apparatus. He wondered at that, it wasn't as though they needed to hide their identities, everyone on board knew everyone else. He paused, unless they had somehow stowed away. That was hardly more plausible than the idea of three or four saboteurs within the crew. Grimacing he tried to ease his aching muscles. Everything about this operation spoke of large scale planning, not to mention serious slip ups in security down the line. He looked up as the intercom chirped again. "Aren't you going to answer that?" he asked lightly, bracing himself as Surreptitious rolled violently.

"There's no hurry," the man behind the mask spoke slowly. "You're not going anywhere."

"Just seemed polite to answer," Tony said carefully, keen to keep the conversation going.

The intercom sounded again and DiNozzo thought he detected a flicker of annoyance in the man's eyes though it was hard to be sure. "He's just going to keep trying," he decided to push a little. "You're holding six hostages, he'll want to know why."

"Who is he?" the man asked and Tony felt a flash of triumph.

"Gibbs," he replied succinctly, seeing no benefit in giving too much away.

"Not one of the crew," the man mused. "Came with you then."

"But have you stopped to wonder why we came?" Tony taunted, deliberately trying to push a little harder.

"Kinda hard to miss when your precious sub stops dead in the water."

"See that's where you're wrong, on two counts actually," DiNozzo continued conversationally. "We were already on our way." Well almost, he added to himself. "We know all about Stevenson and your little plot. Course you helped us out by being sloppy with sabotaging the communications."

The kick, when it came, was not unexpected and he was able to roll away from the worst of it. It was just unfortunate, he admitted to himself when his head stopped spinning, that rolling against the bulkhead left his kidneys exposed to the second attack.

TBS