Shadowhunters One-shots and Preferences

The Finest of Brooklyn Part 1

I've been watching Brooklyn 99 recently and I wanted to do a crossover with Shadowhunters since they're both in the same area (assumingly).
So imagine a random attack takes place in Brooklyn and the 99 are sent to investigate, unaware that this particular attack is Shadowhunter related. The reader is a Shadowhunter in this one.

Some drama, some comedy, who knows what could happen when these two worlds collide. Enjoy.

------99 Precinct-------------

"Alright everyone, listen up," Sargent Terry Jeffords addresses everyone in the bullpen, "last night at approximately midnight, another person was attacked and killed on the streets. And just like the last three attacks, this one's heart was ripped out of his chest. 1PP is on our butts to get this case solved before anybody else gets hurt. So right at this moment, catching this guy is our number one priority."

"Sarge, we have been trying to find this perp for the last month, but so far we have squat," Amy Santiago speaks up, "whoever they are they never leave any clues behind, no fingerprints, nothing." "Yeah, we're all stumped on this one," Jake Peralta quips in, "I haven't been this much at a loss since those arson cases three years ago." "I keep telling you guys it's obviously some sort of Satanic ritual going on here," Rosa Diaz adds, "All we need to do is lure the perp by placing a cam on Scully and when the creep rips his heart out we'll get a good look."
"Uh, I'm not sure how much anyone would desperately want with Scully's heart, given how many heart attacks he has a day," Hitchcock adds. "And half the time those heart attacks are just oopsies," Scully says.
"There's probably no chance of finding this guy anyway, given how well he covers his tracks," Charles Boyle laments.

"Now that is no way to speak during times like this," Captain Raymond Holt speaks as he walks into the bullpen, "Now I know we have no leads, or clues, or any other evidence to go on, but now is not the time to give up, especially when people's lives are at stake. It is moments such as this were we must be at our strongest and most alert. Now is the time we must let the people of Brooklyn know that they can count on the 99 to help in moments of a crisis. Do I make myself clear."
"Yes, sir, you can count on us!" Jake exclaims. "The 99!" Charles adds. "99!" Everyone else joins in. "Now that is what I want to hear," Holt says before directing, "Peralta, you and Diaz will go to the scene of the crime, look for witnesses, camera feeds, anything that can bring us a step closer to finding the murderer."

"I will not let you down, Captain," Jake says with enthusiasm. "Will bring this guy to justice and expose his Satanic cult for the whole world to see," Rosa adds.
"Boyle, Santiago, you two will go to the morgue to see if the body left any clues." "It will be done, sir," Amy nods, Charles smiling in response.

"Oh one more thing I should add before you go," Holt speaks up, "another precinct has been assigned to this investigation, they have already sent one of their own to the crime scene as we speak." "Is it someone we know?" Rosa asks. "No I do not think so," Holt answers, "But if I recall, his name is Luke Garroway."

---------Time Skip to the crime scene-------------

"This is the fourth attack this week," you state standing by the crime scene with Alec and Izzy. The body had been removed hours ago and all that was left were traces of blood and the place was sealed off with police tape. The three of you were had the invisibility rune activated while Luke stood there now playing his daytime role as police detective. 

"And they're getting bolder," Izzy adds, "This was done right next to a mundane bar where anyone could've seen what was happening." "Right now, no one has come forward to say," Luke informs, "with the violence in these attacks, people are getting scared. There's pressure in the precinct to find whoever did this." "Well we already know this is all demon attacks," Alec points out, "but so far there have been no possessions." "Well it's the same like the other three attacks," Luke adds, "Hearts ripped out violently from the chest. Everything else was still intact at the time of the attack." "It would be helpful if we had a pattern to go by," you say, "these attacks can't just be random, what do these people have in common, apart from having hearts?"

"Any chance we can look at the body?" Izzy asks. "Uh, that may take some time," Luke admits. "How's that?" you frown. "Another precinct has taken up this case," Luke explains, "Guess they're getting sick of these killings and want something done about it." "Which precinct?" Alec asks.

To answers his question, two detectives show up on the scene, a man and a woman, oblivious to you, Alec, and Izzy since your three were still invisible.

"Hey," the man calls out, "Are you detective Garroway?" "Who wants to know?" Luke asks. "I'm Jake Peralta, this is Rosa Diaz," Jake answers, "We're with the 99 and here to solve the case of the heart stopping murderer. I know that's not what he's called, I just made that up, so what are we looking at?"
"Well the victim was murdered at around midnight," Luke explains, "heart ripped out of his chest. No witnesses, no fingerprints-"

"And all that's left right now is a pool of blood," Jake finishes, "Oh yeah, this is one dope case I'm looking forward to." "How can this man be excited over a murder?" you frown. "He's a mundane," Alec brushes off, "climbing up fire escapes is enough to excite them."

"So let's set the scene," Jake says, "Care to join me, detective Diaz?" "Jake and Rosa first impressions," Rosa nods, "Blood splatter from against the ally walls suggest the poor sap didn't see it coming when the perp got the jump on him and ripped his heart out." "M.E. reports showed no signs of struggle or a fight," Jake adds, "Further confirms the same poor sap was ambushed. The perp was quick to get the job done. At least the vic didn't suffer too much." "And the perp took the vic's heart to whatever ritual he was holding for his followers," Rosa finishes.

"I'm sorry, what?" Luke seemed confused. "My colleague is under the impression that we are dealing with a Satanic cult," Jake explains. "Which it is," Rosa says with confidence, "I know for a fact there a sick people out there collecting hearts of poor saps that probably have no lives and wouldn't be missed." "Well that was one hell of a dark twist," Jake says with a faux smile.

"Well they may not be completely off," you hypothesize, "Any possibility someone has been summoning demons to collect hearts for something?" "Maybe," Izzy says, "pretty perceptive for a couple of mundanes."
"Maybe we can follow these two, see if they can pull up any clues that we may have missed," you suggest. "You really want to put our investigation into the hands of a couple of mundanes?" Alec points out, "What could they possibly have to offer especially this idiot?" he nods at Jake.

"Hey check this out," Rosa points upwards to what appeared to be surveillance cameras, "Maybe this time we can see for ourselves who is this sicko that's been literally ripping people's hearts out." "Oh yeah," Jake nods happily, "We may have just got our hands on the first clues to finding the heart-stopping murderer."

"Luke, you did remember to erase any surveillance footage about this attack right?" Izzy asks. "Uh," Luke answers, "I think I overlooked those. Which means these two are about to witness something from a horror film."
"Who are you talking to?" Jake asks Luke. "Nothing, no one," Luke assures, "Just talking to myself." "Weird," Rosa deadpans.

You, Alec, and Izzy were about to get the footage out of the cameras but Jake and Rosa beat you guys to it. They take the footage and head back to the precinct.

"Oh man, we are screwed," was all you could say. "We need to get that footage before they watch it," Alec states. "They'll be taking it to the 99 precinct," Luke adds, "You better get going."

The four of you move as quick as you could to the 99.