It's a motive that stretches all the way back to Cain and Abel.
Sibling rivalry was at the heart of Criminal Minds Season 13 Episode 7. But of course, it had its own, freaky little twist.
Or rather, its own slither.
In the words of Indiana Jones, "Snakes. Why'd it have to be snakes?"
The BAU was drawn to Austin in part because of snakes on the plains (of Texas).
Yeah, we got a decently bizarre unsub in Desi Gutierrez. She was the child through which her mother, Laura, learned (a bit too late) what not to do as a parent.
And with her goth look, snake contacts, and scarification, she was a spooky figure.
Abandonment as a child left Desi, not surprisingly, screwed up.
Desi's best friends were her extremely large collection of snakes. That kind of explained why she was so cold-blooded carving up women just to make a heinous point about them.
The BAU's theory was that unsub Desi saw these women as deceptive serpents. I could see why she would feel that way about the mother who largely abandoned her. She abducted her sister to draw out their mother.
But I never understood why she kidnapped and disfigured the first three women since their sins weren't revealed. I'm guessing it was just for practice and to put authorities off her true motivation.
I also wasn't aware of why the BAU shifted from a male to a female unsub. Was ruining a woman's appearance more of a female thing?
Once again, it was Garcia who did the heavy lifting. She received clues such as scarification and tongue splitting, and she rambled through a stream-of-consciousness history of tattooing.
(Coming from her goth background, Garcia has at least one tattoo. She's just too much of a lady to advertise it.)
So Garcia produced the name of Ryan, the one artist who fit all the agents' criteria. It led, in too short of an order, to Ryan selecting Desi from a two-photo array to the agents racing to exactly the right property managed by Laura just in time to stop Desi from hurting her family.
In other words, a case built on the shaky foundation of coincidence.
While it's impossible to condone Desi's actions, it's simple enough see how she got where she ended up. She blamed Laura for her treatment growing up and was jealous of the relationship between Laura and Tina. Mom liked you best.
Somehow, the disfiguring of other women was supposed to carry some kind of message from Desi to Laura. Something such as "See how I can put this community on edge, all by myself." Yeah, that'll show her!
In the end, her plot for revenge against her mother was foiled, and Desi got her back-up wish, suicide by cop, thanks to Matt. I suppose shooting the knife out of her hand was asking too much.
Did Laura make an effort, however feeble, to save Desi from herself? Yes, maybe, but that ship had pretty much sailed already.
So, in the end, Desi made a satisfactory, one-time unsub. Viewers could understand how she got how she was and perhaps feel a little sympathy for her.
When a dead unsub is among the high points of an episode, that's not particularly good. So who stands out among the BAU?
Not Tara, because she wasn't there. And the episode was no worst off for it. I like Aisha Tyler, and it would have been nice if she had been given a three-dimensional character to play.
I'm not sure if Rossi ever left the plane, or if he sat there drinking scotch the whole time. The same could be said for Prentiss. After she barked out some initial orders, I barely remember her.
Sadly, I recall Reid a bit more but not much. He did his Data-with-a-better-haircut routine and made the locals feel stupid, but not much else.
So JJ, Matt, and Alves enjoyed most of the action, with a tipping of the hat to Matt. That's what the young guy on the team is for, to do all the running.
I enjoyed meeting Alves' former partner, Phil, although I have no idea if anything further will be done with him. Garcia taking in the new puppy to give Phil an added incentive to push himself was a highlight.
Garcia continues her warming process with Alves. It seems inevitable they're going to end up the best of friends if Criminal Minds lasts long enough, don't you think?
SPOILER ALERT: On Criminal Minds Season 13 Episode 8, the BAU gets called to Miami when the unsub feeds exclusive footage to the media. Hey, how about the local media doesn't encourage the unsub, but rather turns over the tape to the police?
To catch up before the holiday break, watch Criminal Minds online.
Did you enjoy Desi's story? How about the Alves/Phil relationship? Who would you most like to see take out of an episode?
Dale McGarrigle is a staff writer for TV Fanatic. Follow him on Twitter.