Seen At 11: Risking Your Life To Save A Total Stranger

NEW YORK(CBSNewYork) -- We see it time and time again, people who risk their lives for perfect strangers.

They are heroes who take action without even thinking, but as CBS2's Kristine Johnson reported, not everyone can do it.

In an incident caught on camera, a ferocious crowd showered Iver Whittingham with blows and murderous threats, all because he came to the rescue of a 14-year-old girl who was viciously attacked by an out of control gang of girls at a Brooklyn McDonald's.

"I just had to do something," he said.

Researchers at Yale University who study heroic acts said heroes all have one thing in common, they act first and think later.

"It's not that they think, 'oh man, I could die, but the right thing to do is risk my life here, so I'm just gonna man up and do it,' but much more so people say, 'I didn't think about it, I just did it,'" Professor Dave Rand said.

That's what Whittingham did.

"I reacted the way I would always act, it's just impulse for me, that's it," he said.

That same reaction from the heroes who stopped a potentially deadly attack on a Paris train. Despite great personal risk, they wrestled a gunman to the ground and disarmed him.

Beyond just jumping in, researchers said heroes have another trait; a history of being kind.

"If you've been helpful to people in the past and it's worked out for you then you're more likely to help people in the future," Rand said.

Whittingham fits the bill.

"I just strongly believe in helping people, doing good," he said.

There can be serious repercussions, like retaliation.

"It could be an attack on their property, where they would damage their car, their home, or even threaten their kids," security expert Joe Giacalone said.

Whittingham is still suffering physically.

"I'm going back and forth to the doctors, physical therapy, x-rays, radiology, all types, cat scans, it's hectic," he said.

Still, he said he wouldn't hesitate to save a stranger again.

"Don't be shocked, don't be shocked if you saw me on the news again," he said.

Whittingham had just finished volunteering at an event for a battered women's group when he went to the McDonald's. He insisted that he is not a hero, just a good Samaritan.