THE IDEA WAS hatched as the St. Louis Rams' team bus inched through a rugged part of downtown St. Louis, and, like many of the plans William Hayes and Chris Long come up with, it wasn't taken very seriously. Hayes and Long are the team's jokesters, bantering about everything from the existence of mermaids to opening a plus-size yoga studio.

But this conversation was different. From their comfortable seats in the bus, they saw homeless people on the streets, and Hayes turned to Long and asked him if he thought they could handle living like that. Hayes had been moved by the plight of the homeless since his days in Tennessee when he befriended a man who panhandled near the Titans' practice facility. On the Rams' bus, Hayes told Long he wanted to experience what it was like to be homeless and asked if Long would join him.

They'd turn in their cell phones and credit cards and wander the streets in sub-40-degree temperatures with no place to go. Long, one of the NFL's deep thinkers, gave Hayes a funny look at first, but then he said yes.

"I wasn't going to let him do that alone," Long says. "I'm sure he wouldn't let me, either."

Rams DEs William Hayes and Chris Long went undercover to raise awareness of a life most people ignore. Courtesy of St. Louis Rams

THEY ARE BEST friends with little in common, aside from the fact that they are both enormous 30-year-old men who play defensive end. Chris Long has never wanted for anything. His mother is a retired lawyer and his father is Howie Long, a Hall of Fame defensive end. Shortly after Howie's career ended, he moved his family from Los Angeles to a 65-acre spread in Virginia because they had the means to live anywhere, and this seemed the most peaceful place to settle in. Chris inherited many of his father's athletic gifts, dominated in college at the University of Virginia, and was picked second overall in the 2008 draft.

Hayes wasn't invited to the NFL combine back in '08, and it was a surprise when the Titans selected the unknown lineman from Winston-Salem State in the fourth round. As his parents scrimped to stay afloat, his childhood was full of nos: No, he couldn't have the toy he wanted, and no, this bill couldn't be paid on time. But Hayes had a roof over his head and food in his belly. He was happy. He was showered with love, and never felt as if he was missing anything. It wasn't until Hayes was older that he realized how much his family really struggled.

The thing Hayes loved most about Long is that he never acted like a guy who had everything. "Treat the bellman the same as you treat the president of the United States," Howie Long used to tell his three boys, hoping that privilege wouldn't affect the way they acted toward others.

Long's mom, Diane, always called her son an old soul. He has a bucket list, climbed Mount Kilimanjaro, and started a project to help provide clean water to the underprivileged in east Africa. He has always seen the world differently. But he had no clue what kind of challenges the homeless face.

For the past several years, the Rams' defensive line has donated $1,000 for every sack to the St. Patrick Center, a local homeless resource. Long had never visited the center.

Meanwhile, Hayes became a regular. He took a group of teenagers to the movies and played bingo at the Rosati Group Home, St. Patrick's mental illness facility. This spring, Hayes treated about 15 homeless people to a meal at Golden Corral, an all-you-can-eat buffet.

"I'm telling you, you'd thought they'd died and went to heaven," says Judson Bliss, chief program officer at St. Patrick. "It's very rare for these folks, so it was very special.

"We have a lot of people who give money to us, and that's a good thing. But I think a lot of these social problems that we have, with homelessness and the violence, what it really does take is people being involved in other people's lives. That's what makes a difference."

HAYES IS SO entertaining that some say he deserves his own reality show, and, sure enough, this had all the makings for prime-time television. Long and Hayes wore makeup, hats and second-hand clothing to avoid being recognized. They were followed around by hidden ESPN cameras and were flanked by an off-duty police officer in case they ran into trouble.

Many of these details were hammered out by Nicole Woodie, the Rams' community outreach manager. Woodie went to several thrift stores in search of clothes big enough to fit 270- and 280-pound bodies. She then distressed the clothes to make them look more lived-in, adding dirt and holes.

Hayes and Long wore clothing that had been distressed to make it look more lived-in. Courtesy of St. Louis Rams

Long and Hayes took to the streets on the afternoon of March 22, Hayes in floodwater pants too short for his long legs; Long with penciled-in wrinkles around his eyes. Though the forecast called for a fairly mild evening, the temperature dropped into the 30s. Between them, Long and Hayes had $8 in their pockets.

Surprisingly, neither one was recognized, even when they panhandled for money to buy hamburgers just outside the Edward Jones Dome, their home on Sundays. When night fell, they searched for a place to sleep. Long and Hayes found warmth from a fire in a barrel, but were quickly chased off by a scruffy middle-aged man who said they were trespassing on his space.

They came upon an empty box truck and slept in the back. It provided little warmth, and Hayes couldn't sleep.

"I wasn't scared," he says, "but it was more so the idea of not knowing the next move. I'm trying to close my eyes. We have a security guard with us, but he was like, 'If somebody really wanted to come in here to lift this thing up to shoot all of us and rob us, they could easily do it.'

"Basically, I'm trying to sleep, but I'm trying to figure out what's going to be my next move in the morning. When you get up, it's like, gosh, we've got nowhere to go."

They awoke just after 5 a.m. It rained that morning, and Long said he was glad they were able to experience the elements. Hayes wasn't so enthusiastic. Their experiment lasted about 24 hours. Then they hopped in a van and toured the places they'd gone the day before. When they reached the abandoned warehouse where they'd gone to warm up near the fire, they came upon the man who ran them off the night before. His name is Marty.

Marty ran his own construction business once, but then he split up with his wife, got some DWIs and couldn't get his driver's license back. His life unraveled, and he wound up in the warehouse along with a homeless woman named Nancy, whom he was trying to protect.

Hayes and Long were so moved by Marty's story that they decided to put him and Nancy up in an extended-stay hotel for two months. When Woodie came by to pick them up a couple of days later, Marty was surprised. He said he didn't think anyone would come back. So many times in their lives, nobody came back.

"It's something intangible," Woodie says. "It's like someone believes in them and has hope in them.

"We want this to be the moment that changes their lives forever. We hope that's the case. We also know it might not be."

Hayes and Long bought disposable cell phones for Marty and Nancy and paid for groceries and bus passes.

Marty found a job in construction recently; Nancy received help through outreach support. But it's far more complicated than that. The issues that put them on the streets for years can't be fixed in two months.

Hayes is "absolutely" worried about them, he says. "I can't change the world. They could relapse.

"With Marty, I see he wants to make a difference. I feel like he was getting tired of the lifestyle he was living."

WHEN HAYES CAME up with the idea for this experiment, he did not want cameras following him and Long. He didn't want to make it look like he was grandstanding or being fake. But both Woodie and the St. Patrick Center encouraged him to use his platform to raise awareness of homelessness.

When William Hayes came up with the idea of experiencing the life of homelessness for a night, Chris Long agreed. Courtesy of St. Louis Rams

Both Hayes and Long say the experience changed their lives. Hayes hated the way people stared at him as he walked the streets, judging him by the way he looked. Long used to look the other way when he saw a homeless person. He'd write checks to the St. Patrick Center, but for a long time, he says, the people there were just faceless recipients of his good fortune. Long made his first trip to the facility right after his night on the streets, and promised he'd be back.

"We don't understand," Long says. "We weren't hoping to understand. We were just hoping to gain a little perspective and put kind of a feeling with the cause that we had been [donating to] from a distance the last couple of years."

Long went home that night, rested his head on a pillow in his apartment and stared at the ceiling. He felt warm and lucky, but not quite comfortable. He hopes that feeling lasts.

ESPN's Steve Buckheit contributed to this story.