CARTAGENA, Colombia — This is a story of two unlikely allies, the wealthy executive/mother and the prostitute/drug smuggler, who rescued each other.

The setting is equally improbable and hopeful. A decade ago, Colombia was torn apart by civil war and narco-trafficking. One of Colombia’s problems was an enormous gap between rich and poor, and elites who dealt with poverty by building higher walls around their compounds and topping them with barbed wire.

Yet, against all odds, that ethos has begun to change — with lessons for the United States and the rest of the world. Colombia itself is stabilizing and rebounding, so that, astonishingly, an increasingly popular destination for tourism is Cartagena, which, with its Old Spanish walls and cobblestone streets, is one of the loveliest cities in the Americas.

Colombia still has enormous problems, of course, for civil war has morphed into horrific gang violence in the slums. On one of my visits to a slum, residents said that if I tried to walk around the block, I would never make it back alive. The progress is, shall we say, impressive but still incomplete.

Here in Colombia, one of the successful ones was Catalina Escobar. She was rich, beautiful, American-educated and ran an international trading company. She had a lovely family, including an adorable 17-month-old son, Juan Felipe.

Then, one day in 2000, Escobar received a shattering phone call: Juan Felipe had tumbled over a balcony railing and plunged eight floors to his death.

Escobar spiraled into grief, compounded by something she couldn’t get out of her head. Just a few days earlier, as a volunteer at a hospital, Escobar had encountered a teenage mother who had lost a baby because she couldn’t afford a medicine costing $30.

“I had that in my pocket,” Escobar thought, and she was crushed by the realization that in poor neighborhoods, the death of a child was a common event. Escobar ultimately channeled her grief and empathy by starting the Juan Felipe Gómez Escobar Foundation to memorialize her son and help teenage moms in Cartagena break the cycle of poverty.

Escobar’s foundation reaches out to ambitious girls in the slums, offering them education, counseling, job training, health care and child care. The idea is to give them skills so that they can get solid jobs and a path to the middle class.

The program can be transformative for young women like Yurleidys Peñaloza, who grew up in the slums and is smart, bold and strong. At age 7, Peñaloza says, a relative began raping her regularly. Finally, at age 9, she walked into a police station and announced that she wanted to report a family member for rape. A medical exam supported her allegation, and the relative was imprisoned.

Yet this did not end the oppression of poverty. A few years later, Peñaloza’s mother needed $400 in medical treatment to save her life.

“I thought, ‘I already lost the battle; I’ve been through this, nothing else matters if I can just get my mom through this,’ ” she said. Thus, at age 12, Peñaloza dropped out of school and became a prostitute. From there, her pimp graduated her to drug smuggling. She earned $300 for each bag of marijuana or cocaine she carried from one Colombian city to another, she said.

On one smuggling trip, she and a teenage partner, Katarina, dumped a 10-kilo bag of cocaine while being pursued by police. The drug lords were furious. They shot Katarina dead, and tortured Peñaloza with red-hot iron rods. She still has scars.

Peñaloza started over. By now, a 14-year-old ex-prostitute and ex-drug smuggler, she returned to school and eventually found a place in Escobar’s Juan Felipe foundation, where she has received counseling, health care and training to work in a fancy restaurant. She’s interning as a waitress at a fine coffee shop — where she served me a cappuccino when I dropped by to see her at work.

So Peñaloza seems to have snapped that cycle of poverty, thanks to her grit and to Catalina Escobar. Meanwhile, Escobar has also found a path out of her grief by working with these girls from the slums. “It’s my therapy,” Escobar says.

Colombia has turned around as well. There are many reasons for that, including the leadership of the former president, Álvaro Uribe, and one may be that the country’s elites realized that they couldn’t fully insulate themselves from poverty. Colombia’s wealthy shouldered a security tax to pay for improved policing, and foundations are sprouting to address social problems (although some of that is drug money being laundered).

So bravo to Escobar for turning a tragedy into inspiration, and also for reminding us that rich and poor alike ultimately share the same boat — and the same obligation to help each other.