Current theory:
Single male, college-aged, lives within walking distance. He may be a current student, or maybe just a local who blends in well with the college crowd.
UNSUB is obsessed with murder and serial murder, and his online browsing habits will reflect that, tho he may not ever reveal this interest to others. He feels socially inferior to the residents of 1122, and has likely never had any kind of romantic relationship. He's basically an Incel, but would never call himself that, or belong to any group. While greatly insecure about his social abilities, UNSUB nonetheless feel himself a superior being, with permission to judge and kill others.
UNSUB is a skilled and experienced hunter - very comfortable with blood and killing and knives. Hunting skills include an ability to patiently watch, unmoving, for a long time.
UNSUB came into contact with one or more of the victims thru mutual social contacts - perhaps even at a party at the King Rd house. He became obsessed with the household itself, but because of the timing of Kaylee's return from her parents' house, I feel that she is the main source of his rage, for some reason.
UNSUB spent a great deal of time watching 1122 from a nearby vantage point in the trees; there is an area southwest of 1122 that offers a clear view of the entire back of the house. Google Maps street level of that area is from 2007; it's clear from street level shots from the corner of King and Queen, taken in 2021, that the structure that were in that cul de sac have been torn down, leaving an open area. I've seen a recent photo of the area, showing an abandoned couch, and a clean view of 1122.
UNSUB may have been at the Corner Club on the night of the murders, saw that Kaylee was back in town, and, from listening in the bar conversation, realized she was soon moving away again. He then leaves the bar, heads to 1122, and finding it empty, with perhaps the kitchen slider open, enters and does a walkabout, leaving the window of the unoccupied bedroom on the 2nd floor unlocked for future entry.
UNSUB then leaves the house, returns to the bar, and leaves before K & M do, returning to his own home and then walking to his blind to watch the house. When all the light finally go dark, he enters. Knowing E and X are on the 2nd floor, and not wanting to encounter them on the way out, he kills them first as they sleep - E first, then X, as she wakens in response to E's stabbing (resulting defense wounds).
UNSUB then goes to the 3rd floor, finds K & M deeply asleep, and kills them without a struggle.
UNSUB locks the girls bedroom doors, as well as the kitchen slider, and leaves thru the window he came in by.
I believe he may have left E & X's room unlocked for some reason, and one of the 1st floor roommates looked in their room, called out to them and got no response. She may have seen other things that made her think there was something amiss, and contacted maybe E's brother to check on him, resulting in the 911 call.
Also, UNSUB may have "creepy-crawled" 1122 previous to the attack to familiarize himself with the layout and inhabitants...and the dog.
Here are photo files showing the area I believe he may have watched from. Note the difference between 2007 and 2021
View attachment 383840View attachment 383841View attachment 383842
*The area swirled in the top image is the cul de sac.
