Baltic sea, April 13th, 1982, 0745hrs

            It could be nothing. Carl Lindgren reached forward and polished the screen with a small piece of cloth, using his left hand. At the same time, he wiped the sweat from his right hand on his pants before letting it roll across the tracker ball next to his keyboard. Referred to as an "ape skull" in Swedish Navy slang, the tracker ball allowed him to move the sonar’s directional microphone.

            The sonar would cover most of the 360 degrees around them. Still, this microphone would provide additional sound quality and relay it directly to his headphones and help him evaluate the contact. If he could find it again. Slowly he moved the ape skull, sweeping the microphone back and forth around the bearing where he thought he had heard something. Blank. Nothing at all.

            He cleaned his screen again and blinked his eyes a few times before looking back at it. Nothing. The yellow line, which would indicate a contact, moved slightly with the ocean's background noise but with no indication of a contact. He looked up at the BTR, the printer that would continuously print the contact bearings on a paper roll as the minutes passed. The screen in front of him would tell him the bearing to the contact just now. The printer would tell him where it had been and how it was moving.

            Squinting and running his index finger across it, he was looking for anything that would mark the sound he thought he had heard. Not a thing. He reached for a pen to make a note of the time. That would help him rewind the tape later to see if he could find anything of interest.

            Before he got his pen, another bulge appeared on the round sonar screen in front of him and he quickly ran the microphone towards it. The contact was weak but had appeared very suddenly. Lindgren looked at the time. That makes sense, he thought. He was confident that must be the ferry from Visby.

            "Con, sonar, New contact bearing 175, weak, the bearing is not moving."

            "Understood," the Torpedo officer answered. "Is it the ferry?"

            "Very likely, Sir," Lindgren replied. "Give me a minute to confirm."

            Lindgren briefly closed his eyes and listened to the contact. It was an easy job when you knew what to listen for. M/S Visby would depart Visby harbor at 0730am, pass the outer rim of the pier about 10-15 minutes later, which would remove all barriers for the sound of her engines and propellers to travel far out into the Baltic Sea. Twin screws, currently making only 90 revolutions per minute (RPM), would give her an approximate speed of 8-10 knots. Cavitation was less than many ships her size but still considerable. It would increase as she accelerated to full cruising speed towards her destination, the port of Nynäshamn south of Stockholm.

            Cavitation, the lifeline of the Navy Sonar operator. Often referred to as "cold-boiling" of the water, the change in pressure from the front and the back of a turning propeller blade generated millions of bubbles, like opening a bottle of champagne. As the bubbles collapsed, they made a noise that sonar would recognize as a moving propeller.

            Lindgren pulled out a binder and double-checked the ferry timetable before listening for another thirty seconds. Then he had a look in the Navy ship library, with recordings and characteristics of thousands of ships. M/S Visby had a bent propeller axle, which meant it would give off a squeak for every turn.

            It was easy to find. Lindgren smiled to himself. Someone was stepping on a squeaky toy 90 times per minute.

            "Con, sonar, contact bearing 175, now bearing 176. 90RPM, twin screws, heavy cavitation, axle noise, on time according to ferry schedule. Contact identified as Gotland Ferry M/S Visby".

            That was the end of his official report, but given the ferry and its destination, he added, "Contact likely to turn north shortly and increase speed to 18 knots. She is coming right at us. The bearing will be stable and strength increase over the next few hours."

            "Very well," the torpedo officer said, obviously aware of everything he just heard. Lindgren’s mind had been distracted by the ferry but his body had not relaxed. He had to wipe his hands again before moving the microphone slowly across the bearing of his phantom contact. The lack of sound was worse than anything he ever heard.

* * *

Military headquarters, April 13th, 1982, 0800hrs

            How can you get to the position of the highest-ranking officer in the Swedish Navy and still be treated to shit coffee? Klas Nylund, vice Admiral and head of the Swedish Navy, was not impressed with his reception. He had not been to this part of the military headquarter facilities before and was unsure of the reason for having a briefing here. Undoubtedly the work of the self-proclaimed know-it-alls in intelligence who had set it up. He then took a second to grin at his own thoughts. Judgment about coffee took priority on thinking about why he was here in the first place, at the early morning hours, along with a handful of senior commanders.

            He was interrupted by the Military intelligence commander who walked up to him, did not salute him as they were indoors, but did stand ramrod straight in front of him. Commander Ola Löfgren had started in the Navy but spent most of his career in military intelligence. He did not think much of Nylund, but it came with the job to act in an old-fashioned military manner to please this relic. Nylund was older than his Army and Airforce counterparts, but all three of them possessed the same high-flying view of themselves.

            Without further ado, Ola Löfgren turned on his heels, walked a few steps to the large oak table, and threw a folder on it that landed with a thud. That got their attention alright, he thought, as he sat down.

            "Gentlemen, I know you wonder why I have asked you to this place this morning." There was a grunt of agreement among the officers, now all sitting around the oak table. It looked to weigh as much as a small car. Löfgren was happy he was not the one moving it into place for the briefing. His herniated disc would not have done well with that.

            "There is something we need to talk about”.

            Nylund was now sitting at the end of the table, looking at the intelligence officer with ill-concealed disdain. He had a short impulse to reproach Löfgren to show who was boss in this room, but he was also keen to get to the content of this session. He had lived through the shit coffee, and hopefully, that would not have been in vain. Nylund could not help himself from letting out a sigh and, under his breath, whisper, "Well, let's get on with it then, Commander."

            In response, Löfgren looked at Nylund for a fraction of a section too long before he started. He wanted to make sure that everyone in the room noticed some level of defiance.

            "Well, then," he said as he stood up, walked a lap around his chair for effect, and then looked at his audience. "On April 11th, 0945 to 0953am, a submarine was sighted in Danziger Gatt."

            Löfgren took a breath to continue, but Nylund, already underwhelmed, interjected, "Why are you trying to brief the Navy on a sighting? That runs through our operational office. I haven’t seen anything about Danziger Gatt, by the way.”

            He was pleased when he got a clear nod from Commander 4th surface fleet and what he felt was silent agreement from the rest. Fueled by the audience's response, he continued, "You haven’t been speaking to the lady that saw the last three periscopes from her kitchen window, did you? She is so lonely out there in her cabin she looks for company wherever she can find it".

            The crowd was warming up and Nylund was contemplating continuing his rant. Löfgren was looking at the group without a hint of a smile. With a stern voice, he interrupted, "It did run through your operational office, and you ignored it.”

            The crowd turned silent, waiting for the response of the Navy Chief before daring to commit to a reaction. Nylund shot Löfgren an angry look but did not find any suiting words to go along with it.

            "It was on the surface, and it is not, I repeat, it is not one of ours," Löfgren continued.

            "How can you be so sure?", asked Nylund whose brain just had caught up with the news, only realizing after the fact that this was the wrong question to ask. What did Löfgren mean the Navy had ignored it? Before he got his thoughts straight, Löfgren was well into his explanation.

            "One, because we accounted for all of our submarines and none of them was in Danziger Gatt at this time. Two, one of the witnesses sketched it and sent it to us".

            Löfgren pulled a few pieces of paper from his binder and handed them out. "As you can tell, the shape of the conning tower is completely at odds with a Swedish submarine. I trust this does not look anything like Sjöormen or Näcken to you, gentlemen?"

            Nylund said nothing for a few seconds, mainly as his mind was working out what to do next. He decided to interrupt Löfgren and get some clarity on this.

            “When was this sighting reported, and why have I not been made aware of this?”

            Löfgren flicked through some notes on the table.

            “First report was called in on the 11th at 1010am. Naval operations report requesting a visual scan from the crew at Mällsten. There was also a flyover by a Coast guard airplane that happened to be in the area. Both searches came back blank, and no further actions were taken.”

            That was bad news. Nylund would have to get to the depth of that. He could sense the uneasiness among his commanders in the room on being called out like this. It was not their job specifically to respond to a reported sighting, but somewhere Naval routine had broken down. The sheer number of sightings they got since last year did make it difficult to cope, but if this got out, it would be a major embarrassment for the Navy. Another one to add to the pile since last year. Nylund decided to change tac and go on the offensive.

            With a harsh tone, he turned to Löfgren, "so you have had information on this for two days, and this is the first we hear of it? What the hell have you people been doing? Why were we not informed immediately?"

            Löfgren was now sure he had the upper hand as well as their attention. "Gentlemen," he said with a softer tone than necessary, acting like the adult in the room. "As you know, there are a lot of these sightings passing through the Navy, and before the sketch landed on my desk later in the day, we didn’t know more than the Navy. Once we saw the sketch and questioned the witnesses, it has taken us a fair bit of time to confirm with 1st and 2nd submarine division that this could not have been one of our own". Löfgren paused. "It's not."

            Nylund now struggled to keep himself completely under control. “Why would a sketch like this end up on your desk and not with Navy operations?” he asked acidly.

            “I don’t know, Admiral. Somehow it seems it was handed to the Navy personnel in the guard booth, and that is where it stayed for hours until someone finally brought it upon themselves to walk it up to the main building. Major confusion if you ask me.”

            An intense discussion broke out among the commanders in the room as it was clear more than one thing had gone wrong in the Navy that day. Lack of resources was mentioned. So were the many budget cuts that the socialists had carried out through the past decade.

            "The nationality of the boat?" Löfgren interrupted, bringing them back to the matter at hand.

            Before answering his rhetorical question, Commander Melker Nilsson from the 1st submarine division at Berga interrupted him.

            "There is no way we can be certain based on this sketch. It could be anything. If the sketch is correct, however. It is doubtful to be a Swedish submarine". He continued, "We can speculate in why it is here and who it is. Whoever it is, though, the main question to me is, why the hell is it running on the surface? Except for a catastrophic mechanical failure of some sort, nobody in their right mind would run on the surface in foreign waters". Commander Nilsson leaned back in his chair as if to signal the end of his contribution, leaving a gaping hole in the conversation. The discussion restarted within the group again about the identity of the intruder.

represent a potential escalation? Exasperated?