The Falkenburg animal shelter, 10 miles outside Tampa, is a sprawling facility next door to the county jail; one building is similar to the other. Falkenburg is where the lost and unwanted of the county go. It is where strays wait, hoping to be found. It is the only kill shelter in town. For many dogs, it is the end of the line. It nearly was for my dog, because nobody noticed him.

A month after I lost Riley, I was ready — not for another dog, not right away, but I was ready to start looking for the Next Dog. I had a few ideas about what I was looking for. I wanted a rescue. I wanted a dog who was responsive and trainable. And I wanted a dog who in no way (other than being a dog) resembled Riley. Other than that, I was open to anything — I joked that Next Dog was probably a mixture of Borzoi and Basset. I figured I’d know my Next Dog when we met.

It turns out I didn’t. Not the first time, anyway.

Black-dog syndrome is a peculiar thing. Of any given shelter population, the dogs least likely to be adopted are large, black adults. There are lots of theories. Black dogs don’t photograph easily, I’ll grant that, and these days so much depends on photographs. Some people may think they are unlucky, like the myth about black cats. Some say it’s because black dogs are less noticeable than dogs with flashy coloring. I think it’s a little of everything.

One of the best dogs I’ve ever known was a little black mutt named Buster who, according to the shelter, was a mix of Labrador and Chihuahua. Really, he was. I don’t know how he happened; I tried not to think about it. He was about the size of a Beagle, smart as a whip, and ink black except for a white patch on his chest. We hadn’t noticed him until one of the volunteers pointed him out to my mother. We had a wonderful life with him, and we almost missed it. Black-dog syndrome.

I kept that in mind as I looked for my Next Dog, whoever that was. I looked at the black dogs first. I looked for rescues on Craigslist and Petfinder; I visited a no-kill shelter. I didn’t find Next Dog, but the experience felt healing. It was good to be around dogs. It was good to look at a dog and try to sense if they would fit in my life.

Falkenburg has one goal in mind: to see animals walk out the front instead of being wheeled out the back. There are no lengthy questionnaires or home visits. They don’t ask to legally keep co-ownership of the dog. They don’t have the luxury of demanding these things, because there is only so much room and they are inundated with animals. This is the only place where a person stronger than I could ever hope to be apologizes to the animals before giving them the injection that lets them go. There are worse ways: illness, exposure, neglect, violence.

When I visited Falkenburg, I had a few dogs in mind that I’d found on the website. They name their intake, I assume, because asking for a name is more personable than asking for Animal A-123456. One of the dogs I wanted to see was a little black mutt called Buster, which the shelter described as a Flat-Coated Retriever, though he looked nothing like one. Buster. That felt like a sign.

Despite the air of sadness, Falkenburg is a nice place. The runs are roomy and clean, the kennel wings are ventilated with fans, the dogs have toys and beds. The volunteers were friendly. “I try not to think about what happens to the ones who are gone when I come back,” one told me. “I never ask what happened to them. I wouldn’t be able to keep doing this if I did.”

I walked right past my Next Dog the first time we met. The friend who went with me says I stopped and let him sniff my hand, even. I don’t doubt it. Black-dog syndrome at work. After I’d wandered the kennels, I flagged down a volunteer and asked for Buster the Flat-Coated Retriever. She knew just where he was.

He was a scruffy black dog, about 40 pounds, with a hook at the tip of his tail and a patch of white ticking on his chest. He didn’t bark or jump. He leaned against the chain-link gate at the front of the run, and when I put my fingers through the wire, he licked and nibbled them.

He sat there and stared yearningly at me, pressing against the gate. He didn’t bark. He didn’t paw. He only leaned toward me, as though he wanted out of the kennel and into my lap. His tail wagged nonstop.

Oh, I thought. There you are. I recognized him somehow. I can’t explain it better than that. There you are. You’re my Next Dog. Want to live with me and have adventures?

Adoption at Falkenburg is straightforward. Once you are approved to adopt, you put in an application for the animal you want. Each animal can have two applications, giving it a double chance of walking out the front if the first person changes her mind.

My Next Dog had been picked up as a stray, so he was on a 10-day hold. During that time he could be applied for, and if he was not collected by the person who’d lost him, he’d be adopted out. Most of the smaller dogs and puppies and almost all the purebreds had one application. Some had two. The Next Dog had none, and after I put mine in, nobody else applied for him either.

I called every day to check on Next Dog. Shelter staff told me the people on his microchip had moved to Gainesville. They said they’d given Next Dog away to someone. That person, Next Dog’s erstwhile owner, was never found.

I came back for a visit to do a few more tests. He was pliable and obedient, under all the kennel craziness. He knew sit, shake, and down. He was housebroken. He could catch a ball. He needed a crash course in puppy manners. He was a kisser. He looked like a mixture of Labrador and Border Collie.

At home I tried names, experimentally yelling them across the house. I took Riley’s giant crate out of storage.

When I got the call telling me that Next Dog was ready to come home, it was about a month and a half after I’d lost Riley. It was a sunny day in the middle of October, that strange time late in the Florida summer when the heat is going to break soon — hot and humid like a dog’s breath, but breezy and bright, too. It was a good day to get a dog.

By some strange coincidence, the same man helped me take Next Dog out of the kennel for visits each time. The first time was funny: When the gate opened, the dog shot out, tearing madly down the kennel corridor. I dropped to my knees and called him, and when he slammed into my chest like a treat-seeking missile, I held on until the man could get the sliplead on him. The last time, that same man clapped me on the shoulder and said, “Thank you for saving a life.”

I hadn’t been thinking about it that way, but I suppose I did. I don’t know how long Next Dog would have had once his 10-day hold was up, with no adoption applications filed for him. I’d like to think that someone else would have seen what I saw in him, but I’m not sure. I walked right past him the first time, just like everyone else had. It’s funny, because everyone who meets him falls in love with him.

When I filled out the final paperwork on Gotcha Day, the staff asked me if I wanted to keep the name the shelter had assigned.

Buster. I’d had a Buster once, truly one of a kind, and that name was his. This new dog, this Next Dog, was somebody all his own.

“Logan,” I said. “I’ll call him Logan.”