"We believe that he may have never left the Greater Los Angeles area," says Deputy U.S. Marshal David Siler, who leads a cold case squad focused squarely on capturing the convicted killer.
Eubanks was living and working in Los Angeles under the name "Victor Young" after his 1973 escape from the Ohio State Penitentiary, where he was serving a life sentence for the brutal murder of 14-year-old Mary Ellen Deener.
Investigators believe the fugitive lived off and on with a woman named Kay Eubanks between about 1975 and 1996.
"We're just hoping for that one, one piece of the puzzle that's going to get us to his front door," Siler tells Eyewitness News.
Eubanks bounced around, living at times in Gardena, South Central, Long Beach and North Hollywood. In the late 80s or early 90s, it's believed that Eubanks worked as a janitor at St. Francis Hospital in Lynwood.
Inside the mind of a killer: What investigators have learned about Lester Eubanks
The manhunt for Eubanks spans five decades and he remains one of the most wanted men in America, with the U.S. Marshals posting their highest-ever reward for information leading to his capture, $50,000.
"We know that he has a footprint there, we know that he has associates throughout the area, we just need to talk to those people," says Siler.
Hundreds of new clues poured in after the ABC News Investigative Unit went inside the manhunt with the U.S. Marshals Service for the podcast, "Have You Seen This Man."
Among those clues are photos that Siler recovered showing employees at a former waterbed factory in Gardena, where Eubanks worked during his early years on the run.
The woman who ran the factory, Joy Springer, recalls that Eubanks was hired "right in the beginning of the waterbed era and we were going big guns."
"You had a heartbeat, we'd hire you and put you to work," she said.
Springer knew Eubanks as Victor Young and says that he worked hard, kept quiet and rode a 10-speed bicycle to work. She says that when it rained, she would sometimes offer a ride to his Gardena apartment building on El Segundo Boulevard right across from a golf course.
Another thing she remembers about him: "He wore a lot of cologne and it would give me a migraine," she recalls. "It was overwhelming."
"We would take the whole crew to lunch at Shakey's Pizza," says Springer.
"One of my business partners, she took pictures of everybody, everything," Springer says. "And he was not in any of them, not one."
"One person that we have a name as a possible girlfriend, her name is Renee and she went by 'Sherm,'" says Siler.
Other photos show a former employee known only as Rick.
"We're hoping that the viewers in Los Angeles are able to identify some of these people," says Siler. "I mean they're not in trouble, whatsoever."
"Any information that can get us to that front door, get him in custody," says Siler. "We'll be more than happy to provide them with that $50,000 reward."
One person still hoping for a breakthrough is Myrtle Carter, the surviving older sister of Eubanks' victim, Mary Ellen Deener.
"She was always giggling," recalls Carter. "You know, a little girl. Always giggling and - and having fun."
Mary Ellen encountered Eubanks in 1965 when she ran out of change while doing laundry for the family at a local laundromat in Mansfield, Ohio. She headed out to get change and never came back. Eubanks confessed to shooting her twice in the head. He came back an hour later to finish the job.
"He realized she was still breathing, still alive," says Siler. "He picked up a brick and bashed her skull in."
"It was just unreal," says Carter. "To have a child murdered."
Eubanks confessed to the crime the next day. Within months, he'd been tried, convicted and sentenced to death. At one point, Eubanks was just three days away from execution.
But in 1972, his death sentence was commuted to life in prison without parole. And over time, he earned "honor status" as an inmate and the trust of prison guards.
"That's when the story took a real crazy turn," says Carter. "My mom called me crying... that the sheriff had called her and told her that he'd escaped."
But the escape was not over prison walls. Eubanks and three other inmates were allowed to leave the prison to go Christmas shopping at a local mall - unsupervised. Eubanks simply walked away.
"I mean it just boggles the mind," says retired Capt. John Arcudi of the Mansfield Police Department. "Take him out and turn him loose in a shopping center for rehabilitation purposes? Crazy!"
Siler's focus is on finding justice for Mary Ellen's family and putting Eubanks back behind bars.
"This is one of these cases that you go to bed with, it's one of these cases that you wake up with. It's just so disgusting, so unjust," says Siler. "We continue to fight for her so that someday she will get justice when we're able to put Lester Eubanks in custody."
Carter still prays for justice and that her sister's soul can finally be at peace.
"We went so long with no one caring," says Carter. "I mean, it means the world to me."
The U.S. Marshals are asking anyone with information to call 1-877-WANTED2 (926-8332)
Got a tip? Email ABC7 Investigative Producer Lisa.Bartley@abc.com