When one widow reached her financial and emotional breaking point at the grocery store, a stranger saved the day by paying for all her groceries.

She had no idea who her conveyor belt knight in shining armor was until a cashier tipped her off: “You know that’s Ludacris, right?”

Indeed, it was rapper and actor Chris "Ludacris" Bridges, taking "Southern Hospitality" to a whole new level.

"He taught me that kindness is a currency that we all have. The more you spend it the richer you get."

The star came to the rescue of a struggling freelance journalist, paying for her groceries at an Atlanta-area Whole Foods Monday in a simple act of kindness that has since gone viral.

"I was emotional when I walked into the store and I was out of my freaking mind when I walked out," Therra Gywn-Jaramillo told TODAY three days later.

"He probably thought I was out of my mind. I kept looking at him through my tears thinking, 'Does this guy know he’s an angel?"

Chris 'Ludacris' Bridges is a rapper, an actor... and apparently a secret grocery store angel. Axelle/Bauer-Griffin / FilmMagic

Gywn-Jaramillo said that the 40-year-old rapper’s help couldn’t have come at a better time: She had taken a recent financial hit of $4,000 in one month, made worse by an expected freelance writing check that didn’t arrive.

“It’s just me who is responsible for taking care of everything now — the house, the property, four rescued dogs, two rescued cats, an elderly, blind chicken named Dixie Licklighter, my disabled brother… and myself,” she wrote on Facebook.

“There is no one else to do it. It's all on me. I was too embarrassed to say out loud I was having financial difficulty but it was a solid problem. I was making rice for me and the dogs to eat. I was losing sleep. I was crying daily. I rationed gas in my car…. It was breaking me into pieces.”

Therra Gywn-Jaramillo tried not to let people see how she was struggling, but one stranger's kindness made a huge difference to her. Jennifer Keenan Giliberto

Gywn-Jaramillo told TODAY that in addition to her recent financial troubles, she’s been struggling with the longer-term consequences of losing her husband to brain cancer four years ago and her mother to Hurricane Katrina-related injuries shortly after that 2005 storm.

An sliver of hope earlier this week came in the form of a $250 gift card to Whole Foods from her friend, Mary.

In a quirk of fate at the cashier’s line on Monday, Gywn-Jaramillo’s pet food ended up mixed up with the customer in front of her on the conveyor belt.

Rather than being upset, the man, who identified himself as “Chris,” offered to pay for all of the frazzled woman’s groceries. That act of kindness made Gywn-Jaramillo break down in tears.

"I had no idea when I got in the line that my life was going to change," says Gywn-Jaramillo, who had miscalculated and realized she went over the gift card total. But the good Samaritan wouldn't allow her to put any of the items back.

"He said, 'I got this, all of this,'" she recalled.

They struck up a conversation, and Ludacris, whose real name is Christopher Brian Bridges, complimented Gwyn-Jaramillo for taking care of rescue dogs. But at that point, the writer had no idea who her mysterious benefactor was.

"Who ARE you?" she said she asked him.

"Just a guy," he replied, recalled Gwyn-Jaramillo.

"I basically burst into tears in the middle of a Whole Foods," said Gwyn-Jaramillo. "He’s doing a stranger this incredible— more than a favor. It means more than I could tell him."

After he paid the $375 bill and left, the cashier told Gywn-Jaramillo, “You know that’s Ludacris, right?”

She said the realization caused her to spontaneously belt out Ludacris's tune, "Rollout (My Business),” right there in the store.

Ludacris has been “paying it forward” well before Monday. He founded a charity for at risk youth called the Ludacris Foundation in 2001.

Gywn-Jaramillo vows to follow the "Fast and Furious" actor's example and do kind acts for others.

"He taught me something," she said, "He taught me that kindness is a currency that we all have. The more you spend it the richer you get.

“He gave me a gift that will outlast all of those groceries. He gave me something that is not perishable."