(A/N: Just to keep things simple, Eggman's going to be the only human character in this story, everyone else is an animal just like Sonic and Co, and I will also be using characters from the IDW comics as I enjoy them quite a bit, but this story and it's events are not connected with it's story in any way)
Green Hills City, a fairly large metropolitan area that was named after the very location where was founded, and much like the seemingly endless hills that surrounded it, the city itself was incredibly peaceful. The only things that ever disturbed it's tranquility were the sounds of traffic during it's daylight hours, or perhaps the occasional appearance of the notorious mad man doctor Eggman. Thankfully if it should ever be the latter the populace were never too frightened, as they knew right behind the maniacal genius was the infamous blue blur himself, Sonic The Hedgehog. And while this didn't mean they could just go about their business and ignore the confrontation between the two, it did give them some peace of mind knowing that it'd be over relatively quickly, both due to Sonic's unrivaled speed as well as how experienced he was in dealing with the unhinged villain.
However this was always during the day, there had rarely ever been a time that any citizen of the city could recall, where the two had done battle into the late hours of the night and had disrupted the blissful silence that came with it. For it was when the moon was at it's peak in the sky above, and the stars besides it in the night shined the brightest, that not a single soul could be heard moving about within the city's confines. It was so quiet that you could easily hear the wind blow the leaves of trees, the chirping of crickets, and even the soft hum of the some of the city's signs or lights should you live near them. The only people awake at this late hour were those who sought to watch over this city during it's most peaceful time, from officers who were ready to respond to an emergency should one occur, to the various night guards working in different business and buildings, they were the only ones to see this city in it's undisturbed state as all others slept soundly.
Sadly this peaceful atmosphere is what made it such a prime target for nefarious individuals, and while almost always it was the aforementioned ego-maniacal inventor, there was a new person who had taken notice of how unsuspecting this city was. At first no one even noticed that anything had changed, for several days and even a few weeks everything was as it should be, but then as many expensive businesses dealing in precious jewels or jewelry began to notice their inventory had in fact been switched for expertly made fakes, it was apparent there was a thief at large. This in turn caused the typically relaxed yet vigilant police force of the city to take action, an investigation into these thefts was started and all affected businesses, as well as those not yet struck, had constant police presence to hopefully ward off or catch the thief in action. Yet as time passed by more thefts took place, and not a single officer on duty at the locations hit even realized that anything had happened.
This is when the police realized they were not dealing with just an expert thief, they were dealing with someone who seemed to be an unrivaled master of stealth, someone so capable of being undetected they could easily be a ghost, thus leading them to dub the thief "The Specter". With some kind of name given to the culprit the police then began asking the city's residents if they knew anything, perhaps someone at some point had seen someone they hadn't before, or maybe during these thefts they had also been out at the hour and managed to see something they didn't. Sadly this turned up no evidence or leads much to their dismay and frustration, however they were not ready to throw in the towel and admit defeat, so as a final plan of action they deemed that while the thief was at large all items of great value were to be kept at one location. With this plan in action their hope was that either the thief would realize they were beat, or if they were so brazen and confident in themselves they would attempt another heist, which would give the police their best opportunity to catch them and bring them to justice.
To their credit they did choose the best place to conduct this strategy which was the city's museum, as not only did it have a safe where the valuables could be stored, but it also had a state of the art security system. So in addition to a constantly rotating police force on the premises they also had cameras, a laser detection system both outside and inside the vault, and the vault itself could only be opened at specific times of the day and was built of the toughest stuff around, not even a barrage of high powered weapons could hope to scratch it. Which to those unfamiliar might seem a bit excessive, but seeing as how the city and even the museum specifically had been attacked by Eggman several times, it was honestly perfectly reasonable. Regardless, for a few days after this plan was put to action it seemed to have worked, there were no break ins or theft attempts, and the inventory of the safe was checked daily to ensure all was where it should be, leading them to believe that the thief had finally been bested.
That's when it happened, just a few minutes before the fairly tired officers who had been on duty for the last six hours that night were to be relieved, one of them had decided to do one final patrol near the safe, and as they drew near to make sure all was in order, they found the massive metal door open. Wasting not a single moment they ran to the door and slammed it shut, hopefully trapping the thief inside as they were the only ones in the building at this time. Shouting into their radio to inform their fellow officers in the building, they were quickly in front of the door to begin the wait for when it could be opened again. Thankfully the next scheduled time for when the locks would disengage, would be just a short while after the next rotation of officers arrived.
Though even with there being only one way into the vault, meaning those already present could go home for some rest as the others took their positions, they decided to stay as after everything that had happened they wanted to see who this thief was. But then the time came when the locks disengaged, and as the officers as quickly as they could pulled the door open and poured inside to find the thief, they were met with disappointment and bewilderment. Not only was there no one in the vault as the door opened, but as they took inventory they found that some of the stored jewelry had disappeared. However this entire debacle was not without some reward, for as they began scouring the vault looking for clues, as well as the cameras' footage to see if they could spot something, two shocking discoveries were made.
The first came from the footage on the cameras, for while there were no signs of anyone going in or out of the vault, it did reveal that when the door was opened it had been opened from the inside. This then led to the second discovery, for having found nothing out of place with the walls or the floor the policed moved to the roof, where they found directly above the fault a perfectly cut circle, though it had been filled with the very piece of the vault that had been cut from it. And while this was good news for they now figured out how the thief had gained entry and escaped, this was also bad for it showed whoever this person was they had tech powerful enough to get through their defenses, essentially bringing them back to square one. It was at this point, with still a great deal of valuables left in the museum's walls, that the police decided to finally bring this matter to the one person who had dealt with high tech gadgets and weapons more than anyone else.
"And that's pretty much it." The chief of police concluded, as she closed the open file on her desk.
Having spent the last hour doing nothing but talking, it was rather impressive that the chief wasn't out of breath and had managed to keep her composure, especially with how frustrating this whole situation must be for her. In appearance she was a dark crimson hawk with bright golden eyes, combine this with her police attire and demeanor, and even the bravest person might find themselves a tad bit nervous in her presence. Thankfully her current company were far too familiar with fairly intense and scary situations, to her right stood a young yet incredibly intelligent yellow fox named Tails, and to her left the very hero of the planet who she had sought the aid of regarding her current dilemma.
"Hm, what do you think Tails?" Sonic asked with a raised brow as he looked over to his companion, who seemed to be in deep thought pondering the information.
"Whoever is committing these thefts is definitely using some impressive tech, however I don't think we're dealing with Eggman, far too quiet and subtle for it to be him." He responded.
"Yeah, if it were Eggman he'd probably just rip the vault from the bank, heck he might even try to pick up the whole building and take it with him if it had something he wanted." Sonic joked.
"Right, but seeing as how the only things this thief seems to want are jewels and jewelry, none of which have any special properties of any kind, it's obvious that all they're looking to get from this is rich." Tails reasoned.
"Which is exactly why we asked for your help." The chief interjected, regaining their attention "We have spent nearly a month trying to apprehend this criminal ourselves, only to be constantly left with no results and fewer valuables as rewards for our efforts, I know this isn't as exciting as fighting a giant robot or saving the world, but we are in desperate need of your help." She admitted.
"Hey don't sweat it, if anything this happened at the perfect time!" Sonic exclaimed excitedly, earning a slight glare from the chief "Hehe, what I mean is that Eggman's been kinda quiet, and while that doesn't ever mean anything good, this at least gives us something to do before he carries out his next big scheme, not that we wouldn't help you if things weren't quiet, just...you know." He awkwardly explained, as her unwavering glare was digging into him like daggers.
"Anyway, I'll get to work setting up some traps and surveillance of my own at the museum in addition to it's pre-existing systems, with permission of course." Tails suggested.
"By all means do what you believe is best, just so long as this thief is finally brought to justice and we can hopefully recover the stolen items, then you have my blessing to do whatever is required." She told them.
Nodding in reply the duo then turned around and left her office to get started, as they only had a few hours before the sun would set over the horizon and bring with it not only the cover of darkness, but the ever elusive Specter who they planned to catch.