Thousands of country music fans fled in terror on Sunday as bullets rained down on a concert in Las Vegas.
But many stood to face the terror head-on, including one man filmed opening his arms and shouting "come on p******" as gunfire crackled around him.
Several others were filmed staying on their feet, including one man who gave the finger before taking a sip of his beer.
The focus of their anger was Stephen Paddock, 64, from Nevada, who police said carried out the massacre shortly after 10pm (local time).
Officers say Paddock fired on the Route 91 Harvest Festival from the 32nd floor of the Mandalay Bay Hotel where he had been staying for days as he planned the atrocity.
He shot himself dead as officers surrounded a room where he had amassed an arsenal of at least 10 rifles.
Before killing himself, Paddock got into a firefight with police, leaving one in critical condition, and another with minor injuries.
The critically injured officer is now stable after surgery.
Investigators have raided Paddock's $400,000 home in a nearby retirement community, but say they have no word on his motive.
Isis has claimed responsibility for the attack, saying Paddock converted to Islam months ago, but the FBI has since said there is no indication he was part of any foreign terror group.
Witnesses described seeing off-duty service personnel and police officers plugging bullet wounds with their fingers after the attack.
Russell Bleck said as concert-goers hit the floor, police stood tall to direct people to safety, risking their lives to save others.
Other videos showed thousands of people fleeing in terror while others sheltered behind whatever cover they could find.
The wounded were rushed to safety using office chairs, wheelbarrows, or were simply slung over people's shoulders as the chaos unfolded.
President Donald Trump addressed the nation after the attack, calling it "an act of pure evil".
"Scripture teaches us, 'The Lord is close to the brokenhearted and saves those who are crushed in spirit'," Trump said. "We seek comfort in those words but we know that God lives in the hearts of those who grieve."
Trump also announced that he would travel to Las Vegas tomorrow. Meanwhile Eric Paddock, Stephen's brother, said there was "absolutely no indication" that he was about to do something like this.
"He was just a guy. Something happened, he snapped or something."
Speaking from his home in Orlando, Florida, Eric Paddock said: "We know absolutely nothing. This is just... we are dumbfounded.
"We have absolutely no idea. Our condolences go to the victims and all their families."
He added that his brother had "no political affiliation, no religious affiliation, as far as we know" and that he'd never been "an avid gun guy at all", adding that he was at a loss as to where Stephen got his arsenal of automatic weapons.
"He has no military background," he added to CBS News.