It is a strange story.

A 27-year-old tourist was attacked in broad daylight on the street outside of the Lyric Opera last month.

Mark Ball, 50, has been charged with allegedly beating the man who was vacationing in Chicago. According to the Chicago Sun-Times, the victim was kicked and punched in the face as he lay curled up in a defensive position.

As of yet, no motive has emerged for the beating. But Robert Hartge, one of the men credited with intervening in the attack, said he and three other stagehands tried to break up the attack.

Hartge said he followed the attacker for a block and was eventually able to “flag down” transit police officers who held the alleged attacker until Chicago police officers arrived.

All this happened at the time of the day when dozens of office workers are streaming toward Starbucks in search of an afternoon pick-me-up.

But Hartge told the Sun-Times while there were “people everywhere,” they ignored the violence.

“Their blinders were on,” he said.

Shocking.

Many of us are quick to accuse residents in crime-ridden neighborhoods of looking the other way when bad things are happening.

We like to think to that we’d be among those who are brave enough to report those bad things. It doesn’t matter that when it comes to urban crimes, the criminals usually live within several blocks of their victims.

We expect anyone who sees a crime being committed by his or her neighbor to call police. When there’s a fatal shooting, particularly one involving a child, law enforcement often urge residents to break the so-called no-snitch code by identifying anyone connected to the shooting.

But a tourist was pummeled in downtown Chicago and plenty of Chicagoans walked on by like it wasn’t their business.

Obviously, this is the kind of story that gives the mayor heartburn.

It is one thing for the media to stereotype neighborhoods like South Shore and Chatham as unsafe.

But downtown, with its Millennium and Grant parks, world-class museums, architecture, theaters and restaurants, has long been branded as part of the “Other Chicago,” where there is an expectation of safety.

Yet, crime spreads like a virus.

The man accused in this downtown attack told police he lives in the 8800 block of South Michigan. According to the victim, his attacker allegedly followed him on a downtown street and knocked him to the ground.

Given the huge crowds of people that travel across the loop like a herd of cattle, it is hard to imagine only one man followed the alleged attacker.

Does this mean that people are so tuned into their smart phones that they don’t look up when someone is being attacked on the street.

Did they think the men were involved in a personal relationship and, if so, what does that say about how we view domestic violence?

Coincidentally, this year marks the 50th anniversary of the infamous Kitty Genovese murder in New York City.

Genovese was a 28-year-old bar manager when she was stabbed to death at 3:15 a.m. in the vestibule of her apartment building.

The murder sparked worldwide outrage when The New York Times erroneously reported that 38 of Genovese’s neighbors had watched the attack and did nothing.

Although the number of people, who actually watched the young woman being stabbed, has been challenged over time, the Genovese murder is symbolic for community apathy.

But the lessons of the Genovese murder have apparently been forgotten.

For instance, in 2012, an 86-year-old World War II veteran was beaten and carjacked in broad daylight at a Detroit gas station, and citizens allegedly did nothing.

Is that how we want to be characterized?

Chicagoans need to unplug and start paying attention.

When it comes to crime, no one should have blinders on.

Email: marym@suntimes.com

Twitter: @MaryMitchellCST