[Updated at 2:30 p.m. ET]
The video is heartbreaking: a pack of junior high boys berating a 68-year-old school bus monitor in upstate New York. She's brought to tears as the students pepper her with profane put-downs about her weight, age, livelihood and more.
"You're not sweating?" one kid asks her. "Why's there water down your face?"
"I'm crying," she responds.
"She probably misses her box of Twinkies," taunts another boy.
But for all the bad brought on by the juveniles, comes an even better story of compassion and goodwill.
The viral video, which one of the boys reportedly posted on Facebook, has caught the attention of scores of people who've pledged more than $200,000 (as of Thursday afternoon and growing) to send Karen Klein on a vacation.
The astonishing outpouring of support was started by Max Sidorov, a 25-year-old Toronto nutritionist who saw the video and on Wednesday launched a campaign on the crowd-source fundraising website Indiegogo.
"She doesn't earn nearly enough ($15,506) to deal with some of the trash she is surrounded by," Sidorov wrote on the site. "Let's give her something she will never forget, a vacation of a lifetime!"
His initial goal of $5,000 was shattered within hours. Strangers from around the world have shared the story on social networks and pledged amounts of $5 to hundreds.
"Karen, I am sorry for what you have endured," a woman commented on the campaign page. "Humanity and kind heartedness does still exist."
Sidorov says he knows why so many have responded so quickly.
"Bullies," he told the Los Angeles Times. "That's the real reason. People want to stand up for the little guy, and everybody just forwarded it. I just had a good idea, and everybody else took it and ran with it."
Klein, a grandmother who drove a school bus for 20 years and has been a monitor for three, said she's "kind of numb" from the generosity.
School officials and police in Greece, N.Y., are now investigating.
"Sometimes you expect kids to be like they acted, but not that bad. They weren't that bad all year," Klein told WYSR-TV. "That one day, I don't know what possessed them."
The father of one of the boys has apologized.
"My heart broke," he told ABC News. "I couldn't believe my son could treat another human being like that."
Nor can a network of good Samaritans who have righted a despicable wrong.