Dusk is descending upon Salt Lake City.

As the shadows elongate and the sun sinks behind the Oquirrh Mountains, they take to the streets.

The costumed avengers start at the Salt Lake City Library and fan out. Always in groups of at least two, they are on the lookout for trouble.

They happen upon a mother and grown son in a screaming match on their front lawn.

Calmly, the masked men walk into the fray, saying nothing.

The son backs down, gets in his car, and tells his mother he’ll be back later.

They’re not millionaires out to avenge their parents’ deaths and none of them has been bitten by a radioactive spider. Nevertheless, they say they are helping in situations like the one they described above.

Most of them are tattoo artists from Ogden who claim they are atoning for past lives that include alcoholism, gang life and being the muscle for drug dealers. Others say they do social work or lease apartments and just wanted a unique way to do service.

The group, called the Black Monday Society, formed about five years ago when founder Dave Montgomery, who started calling himself Insignis but recently has changed to Nihilist, had stopped drinking for about six months. He found the members of the Society through a website claiming to bring together real-life superheroes and met with some who lived in Utah. Within six weeks, they were roaming the streets.

"It was as addictive as any drug," said Montgomery, who dresses in black leather with silver studs. "You fall into a whole other self."

The name comes from the idea of being able to turn someone’s bad day into a good day, he said.

The group started with just two people, but quickly grew, peaking at 19 members, all of whom came with their own uniforms, superhero name and backstory worthy of any comic book. Nearly everyone in the society has a tattoo that’s given after completing a certain number of patrols.

But when it’s real life — balancing families, significant others and jobs — the burnout rate is high.

The group now has nine men who patrol downtown Salt Lake City at least a couple of times a month, but they are careful to distinguish themselves from what people see in the new Batman series or the movies "Kick-Ass" and "Watchmen."

"Those movies have done more damage to the real-life superhero community than anything else," said Mike Gailey, the 6-foot-1-inch, 245-pound man who goes by Asylum. "You can’t just go out and beat someone up for jaywalking."

In the five years they’ve been together, they’ve never come to blows with anyone, they said. A check of Utah court records shows no criminal history for any of the members in the state.