BLACK BEETLE : 1, THEO AND IRENE : 0

I spied a black beetle crawling across our livingroom floor a few minutes ago...how this beetle got into the house I don't know, but there he was in the near presence of not one, but two dogs that will eat damn near anything. A recent example: Irene gutted an empty dog food bag that I had used as a trash bag the other night, among the contents: 2 week old mac and cheese, a couple of frozen eggs (broken) and a variety of leftover science projects from the depths of the fridge. All covered with used coffee grounds and ashtray offerings. We awoke to find this trash spread across our kitchen with nothing "edible" left, even the paper plates used to soak up the oil from the frying had been chewed on. It was all gone, even the fuzzy blue green whatevers. Irene is the dog that will kill a rat and eat it.
Theo is close, but prefers counter surfing and stealing more fresh junk, he likes plastic.
I point out the beetle to Theo, who approaches, sniffs and turns away. No snorting or foaming at the mouth, no grunts or barks at the little black thing traversing the floor. He just turned away and gave me a look and got back in "his" chair. Ditto Irene, she approached the beetle with enthusiasm, but backed off right away and allowed the beetle to go, unhindered by sharp pointy Irene teeth ( she can bite a rat in half with ease) under my ottoman.
So, what does this beetle have that countless crickets and junebugs and cock-a-roaches don't? What spared this beetle a future in a dogturd in our backyard, little black shell parts glistening in the sun in contrast to the brown byproducts of purina small bites?
It wasn't a stink bug or an assassin beetle...humans can smell them when they release the defense shield from a fair distance, and they have both been consumed by both dogs...hell, Theo has been known to eat yellowjackets.
What kind of chemical did this black beetle release to ward of predators a kagillion times it's size?
I don't know, but whatever it is, I want some. I'm gonna go find him and put him back in the yard now. That beetle has balls.