I initially believed my dog had gone crazy when he started climbing on top kitchen cabinets and growling loudly lately, but then I understood what he was howling at 
This was the most unusual behavior from my dog. Rick was a calm, intelligent dog that had never barked without cause and had always complied with me. However, during the last few weeks, he started barking at night, standing on his hind legs close to the kitchen cabinets, and—most odd of all—climbing onto the upper shelves, which I myself hardly ever visited.
I initially attributed it to stress or aging; perhaps there was a cat hiding there, or perhaps the noise was coming from the neighbors. He was aware that it was forbidden to climb on furniture, but his insistence was unnerving. Nevertheless, he sat there defiantly, glaring at the ceiling and snarling gently, as though to warn me of something crucial.
— “What’s it, friend? What’s that up there? — Kneeling next to him, I asked. He raised his ears and turned his head. He gave a harsh, short bark. And he barked louder each time I attempted to approach.
Rick’s barking got louder one night and he started whining persistently. I could not endure another restless night of hearing noises that only he appeared to be able to hear; I was sick of the tension.
I took the old folding ladder from the storage closet, put on a jacket, and got my flashlight. My heart was racing in an odd way, perhaps from frustration or anxiety, or perhaps because I was ready to stop this.
Rick stepped away softly but purposefully, looking up. I ascended. I don’t believe I had ever noticed the ventilation grille hanging a little off-balance before. “Finally — must be a mouse or something trivial,” I thought. As soon as I took off the grille, I noticed something horrifying
There was a man in the dark duct behind it. As if he had been hiding there for centuries, he was hunched down, his face smeared in dust, his eyes filled with fear.
Gasping for air, he began to move instantly and attempted, but was unable, to stand. He had a few tiny stolen items in his hands, including an unclaimed keychain, a cellphone, and an empty wallet.
With shaking hands, I reached for my phone and dialed 911. My voice trembled as I spoke, but the dispatcher understood when I said, “There’s a man hiding in my ventilation system.” Please arrive as soon as possible!
Rick was constantly smelling the vent and waving his tail as I was speaking, as if to check that it was indeed him.
The police showed up in a flash. After carefully removing him, they placed him on a blanket and monitored his breathing. His arms were cut, his eyes darted around in a panic, and he was pale and tired.
From around his neck, one of the officers took a modest treasure: a silver necklace with an initial-engraved pendant. It was most likely missed by someone out there.
Then the inquiry started. As it happened, this individual wasn’t the first to use our building’s ventilation tunnels.
When the local officer questioned the neighbors, they instantly recalled odd disappearances: one couple reported missing jewelry, another lost a bank card, and another a pair of rings.
No evidence of forced entry was found. But he had slithered through the dark, cramped hallways between floors, sly and nimble. He would pick the smallest, least obvious items at night because they were quick to remove and simple to conceal.
