(CNN) As throngs of passengers boarded the plane, a cacophony of barking could be heard coming from the belly of the jetliner. The packed flight was getting ready to depart San Juan, Puerto Rico, for New York, and almost two dozen canines were being loaded into the cargo hold.

These Satos were about to depart on their "Freedom Flight" to New York.

Sato is a Puerto Rican slang term for street dog, and the dogs aboard the flight were about to star in a dramatic rags-to-riches story.

"That's the point where I always wish I could have a conversation with them, and that they could understand me," says Chrissy Beckles. She wishes she could tell them "that this is gonna suck, and you're gonna be frightened, but it's gonna be four hours. And once you land in New York ... life just becomes spectacular."

Beckles is the founder and president of The Sato Project , a nonprofit group that rescues dogs from "Dead Dog Beach" in Yabucoa, a town in southeastern Puerto Rico.

The beach's name is not an overstatement. Some of the dogs are in bad shape even before arriving on the beach; they're underweight, covered in fleas or infected with parasites. Others are perfectly healthy animals that appear to have been family pets.

"Some of the conditions that we've found dogs in ... there's no way that they could physically walk here," says Beckles. "They have been driven here and dumped."

The dogs are left by people who can no longer care for them or who seemingly choose not to.

Playa Lucia

The real name of "Dead Dog Beach" is Playa Lucia. It was once a popular spot for beach-goers, with a pool and cabana facilities. But the pool is now filled in, and the building lies in disrepair; it's covered in graffiti and mounds of trash abound. Sun-worshipers are now sparse, having long since been replaced by satos. Beckles says at one point there were as many as 300 dogs roaming the beach in packs.

The day we meet Beckles, she and her team are planning a rescue mission on "Dead Dog Beach." Three adolescent siblings that look like wire-haired Jack Russell terriers are the day's targets. They live in a thicket that surrounds the beach and won't allow humans to get close.

Patience and experience are the name of the game. The team spends nearly two hours luring the dogs out of the jungle with food. Hunger, or gluttony, leads one of the dogs to an open rescue crate with chicken inside. He takes the bait, and the door is closed behind him.

Bam Bam

Like all the other rescues, he's immediately given a name: Bam Bam.

"Give him a couple of weeks, and he's gonna be livin' the good life," Beckles says.

But the day is not without surprises, as is often the case. A Sato Project volunteer finds a pregnant basset hound mix nearby who is clearly close to her delivery date. She had to have been abandoned in a flash; Sato Project volunteers patrol the beach at least two times a day.

"It happens very, very fast," Beckles says. "A car has driven (by), dogs have been thrown out, and they've just kept on going."

The temperature in Yabucoa is in the 90s; there is no water and very few places to find relief from the heat. Even in the shade it's sweltering hot. The pregnant dog, now known as Evelyn, needs help urgently.

Beckles and team veterinarian Dr. Bianca Aguirre-Hernandez do a preliminary check and find Evelyn is healthy and clean. She's also not afraid to be placed on a leash -- she was clearly someone's pet.

Evelyn

All of the dogs rescued off "Dead Dog Beach" are taken to Candelero Animal Hospital in the municipality of Humacao, where Aguirre-Hernandez practices.

It's here that they receive a full examination and treatment, and where they start their road to a new life. Most dogs take about 10 weeks to rehabilitate.

Bam Bam, for instance, turned around pretty quickly at the clinic. "Once they learn that not everyone is going to harm them and that they are safe, loved and taken care of, then dogs begin to trust," Beckles says. "It's always a beautiful thing to witness."

Others are at the clinic longer. Beckles says a number of dogs have had to stay over a year before they were ready to be relocated.

The clinic gives The Sato Project services and living space for the dogs at a discounted rate. Beckles says the average cost of rescuing one Sato is about $1,000. But one dog, Adrian, cost the nonprofit $20,000 for rehabilitation alone, according to Beckles. An injury to Andrian's leg required extensive medical care, and she's still a work in progress.

While Adrian may have been one of their most expensive cases, Victor Amor is the group's most challenging -- and perhaps most rewarding.

Victor Amor at Candelero Animal Hospital

"He was just a bag of bones under a palm tree in the pouring rain," says Beckles. He suffered from severe malnutrition, anemia and mange, a skin disease caused by parasitic mites. According to the emergency doctor who treated him, he had little chance of survival.

Victor Amor at his adoption

"This dog was essentially dying in front of me," Beckles says. "I asked him to fight. And I begged him to fight. I said, 'If you fight, I will fight with you, and we will do whatever it takes to get you healthy and happy.' "

The organization's motto is "We fight so the dogs of Puerto Rico don't have to." It's a motto that Beckles takes quite literally.

She's a champion amateur boxer who puts on her gloves on to raise awareness and money for the organization. The Sato Project's New York headquarters are housed at the famous Gleason's Gym in Brooklyn. It's Beckles' base of operations -- and where she trains.

In July, she took to the ring for a fundraiser bout and her punches were no joke.

"I'm very inspired by the fight that these dogs have in them. ... I look back at some of the dogs that we've rescued, and I figure if they can do it, then I can certainly take one more hit for them."

Beckles won the match after three intense rounds, and the event raised approximately $60,000 in the process.

She says more than 1,400 dogs have been rescued from "Dead Dog Beach" since she started The Sato Project in 2011. But not every case has a happy ending. On a handful of occasions, Beckles has had to make the call to euthanize dogs that she says were beyond saving.

She says those days are tough, but the good days make it all worthwhile.

Every dog is removed from Puerto Rico after his or her rehabilitation. Most of them are flown in cargo on commercial flights to New York. But some have gone to other locations, including Los Angeles, Las Vegas, Boston and Vancouver. One even flew by private jet to Bermuda, Beckles says.

During our visit, 23 dogs are flown to New York. The transport operation is done with military precision: Beckles, Aguirre-Hernandez and a group of volunteers start prepping the dogs before dawn. They are tagged and crated and driven to the airport as the sun rises over San Juan. Once at cargo, the volunteers say their good-byes.

"There's usually tears," Beckles says.

The dogs are met at John F. Kennedy International Airport by another set of volunteers, foster families and workers from local shelters who take in the dogs for adoption.

Evelyn with her forever family

Bam Bam, Evelyn and Victor Amor are all placed with loving families.

Bam Bam's new home is in Connecticut. Beckles says he spent part of the summer vacationing in Nantucket. Evelyn lives in New York with a family that first took her in as a foster dog but adopted her soon after. Her seven puppies are all healthy and will soon arrive in New York for adoption as well. Victor Amor lives on Long Island; his new family includes another Sato Project rescue.

The Sato Project's ultimate goal, Beckles says, is to make Yabucoa, the home of Dead Dog Beach, a dog-friendly community and model for other places with similar issues. She also has a plans for a spay and neuter program -- something that will require a lot more funding. That might mean Beckles has to take it on the chin for the dogs of Puerto Rico a few more times.