Rutinal Tower patrol outside the borders of Black Garden system. Single Infield class was cruising slowly around one of uninhabitable planets  that were kind of common there. This one was a red gas giant - Nearly as big as sun that it was orbiting. Due to some... strange effects and mixes of gases on said planet, normal sensors were useless - Informations were far away from truth, if even able to get at all.
Planet was signed as a danger for Tower, since there was enough space for little pirate fleet to hide. That's why patrols had to fly by the red giant. After all, Tower wanted to avoid problems with outlaws - by exterminating them.
Crew from Tower's ship wasn't expecting to find there anything  at all. It wasn't important system in any way - so activity of any civilized race was rare. You can imagine how surprised, as well as scared they were upon noticing an actual ship behind the planet.

Large unit with somewhat bright paints was just floating slowly behind the gas giant, scaring with it's weaponry. Definetly a destroyer class ship. Of course patrol crew were just about to turn around their cannons and barrage the ship with a nice salvo - what wasn't really professional like for Tower's soldiers, damn cadets - when captain of our patrol vessel realized that the ship was heavily damaged, and most probably was lacking any crew at all.
Heavily bent sheets of metal were getting off the hull, if they were even at their places of course. Cut cables were sending off sparks from their ends, while weapon systems were lacking actual weapons. No need to add that there was a large hole in ship's centre - it's a mystery how it even managed to hold two sides of vessel together.

A hour or so has passed, while patrol vessel was just wandering around the destroyed ship. It was quite nice find actually, you don't find a debris of military-purpose ship everyday. And since Tower was lacking units in it's fleet, so every additional unit was for the weight of gold. Or at least a design of one - repairs would be probably... problematical to say at least.
A little fleet of Tower's ships jumped into the system, soon getting behind the red planet as well. Logistical officer that was leading the fleet had a simple order - bring the ship back to the Black Garden. How he was about to do this, well that was other question.
Three little dropships were sent from one of the Porter class vessels. Slowly getting closer and closer to the destroyed ship, specially prepared Volunteers aboard were preparing to check the ships insides.

Boarding teams soon has made their reports to the action superior - and as you can imagine, they didn't really find anything interesting at all. Well, maybe except fact that whole ship didn't had any signs of inside fight, boarding, virus - Literary nothing. there weren't even any corpses of last crew, while majority of terminals were destroyed, making databanks useless without specialised equipment.
However, there were also good news - Engines were somewhat working, while bridge was untouched. Only few simple repairs here or there were needed to bring the ship back into mobile state. That was making whole situation a lot easier, since Tower didn't had to tow the destroyer with own ships.

Another two hours of intense work and repairs have passed, and destroyer was eventually able to move by itself. Now filled with few crewmembers that were trained in moving around the bigger vessels, it could be brought back to the shipyard. Slowly. Very slowly. After all, it would be a shame if damage would be so big that the ship would break in half due to speed, so it was better to be slow than sorry.
And so, an Xeno destroyer has moved out from it's hideout, slowly cruising towards the Black Garden system. It will be a long trip, everyone present in this little fleet was aware of it.
They couldn't just jump back to their home system - it would be devastating for the ship, and probably deadly for crew aboard. And estimated time of they arrival was in about a week. Well, somebody had to do it.

Everything was going on smoothly, no real problems occurred during their "trip". Well, they had to receive additional supplies from another logistical fleet, since they have packed a bit to little of supplies for their crew. Except that, nothing was a serious problem.
Tower had some time to examine the ship in meanwhile. Engineers has examined the damage status on the whole ship - And apparently, it seems that it was shredded by energy beams. Nothing new, right - many ships in universe had energy based weapons, after all they were pretty much ammunition-saving. However, their problem was a little bigger - it turned out that the main hole in hull was also caused by beam weapon. Single beam, to be more exact. What kind of battleship could have such a devastating weapon? It wasn't a good information for Tower - After all, it was another possible threat to deal with. And this time, the treat was able to cut their ships into half with a single salvo.
Another interesting thing - Ship was carrying some kind of experimental weapon system inside. Single high velocity cannon, running across the ship's centre. Actually, if not the hole in hull, they would probably be able to see how it works - but half of the barrel was gone. They will need to wait this time.