(FORTUNE Magazine) – Around 6 a.m. on Jan. 9, 1993, a phone call roused Frank Portillo from his sleep. It was a field supervisor at Portillo's company, Brown's Chicken & Pasta, based in Oak Brook, Ill. "Turn on the TV. You've got a problem in Palatine," Jeff Zavoral told his boss. News reports said there had been a possible murder at a Brown's franchise in the quiet suburban town. Portillo jumped in his car, picked up Tom Kennefick, vice president of Brown's, and sped to the scene, 45 minutes away. Police had cordoned off the restaurant, so Portillo drove to the Palatine police department, where investigators were beginning to piece together the crime. Two suspects had entered the store around closing time the night before and murdered Portillo's two franchisees--Richard Ehlenfeldt, 50, and his wife, Lynn, 49--and their five employees: Thomas Mennes, 32; Guadalupe Maldonado, 46; Michael Castro, 16; Marcus Nellsen, 31; and Rico Solis, 17. The victims had reportedly been forced into walk-in refrigerators and were shot with a .38 caliber revolver. The perpetrators also cut one victim's throat and stabbed another in the stomach before stealing about $1,800.

Portillo, a trim, youthful man who at 68 wears his graying black hair in a ponytail and dresses in silk shirts, had faced plenty of obstacles as he'd worked his way up from poverty. He'd partnered with chicken farmer John R. Brown to build a fast-food chain that at its peak in 1987 had 100 restaurants. But as he struggled to cope with one of the worst crimes in the history of the Chicago area, the once-single-minded entrepreneur was about to face the challenge of a lifetime. With the TV news broadcasting stories about the "Brown's Chicken & Pasta massacre" night after night and the perpetrators on the loose, frightened customers stopped coming. The business he'd devoted his life to teetered on the brink of bankruptcy. "It was hell," says Joan Portillo, his wife of 50 years, her voice breaking. "H-E-L-L, in capital letters. I want to forget it."

Nearly ten years later the crime may finally be solved with the arrests of two men, and Portillo is rebuilding. What got him to this point was his ability to channel the determination that had made him a successful entrepreneur into a one-man crusade to pressure the police to solve the crime. At times he drove himself so hard that he couldn't sleep, forgot to come home for meals, and found himself breaking down in tears in the middle of the day. But in the end his relentless efforts paid off. Portillo saved his business--and maybe his life.

Until the murders at Palatine, Frank Portillo's story fit the classic contours of the American dream. The second child of Frank Portillo Sr., who had crossed the border from Durango, Mexico, at age 16, and Beulah Docas, who had come from Greece by way of Ellis Island, he grew up poor and lived with his family in what are now known as Chicago's Cabrini-Green housing projects. After marrying Joan Valdivia, his high school sweetheart, he got an entry-level job as a draftsman at Northern Illinois Gas Co., working his way up to field engineer. But without a college degree, his prospects for advancement were limited. Portillo began toying with the idea of going into business for himself when chicken farmer Brown, a friend of his father's, hired him to design a more efficient version of Brown's Fried Chicken, a takeout restaurant he ran in Bridgeview, a suburb of Chicago. The young man worked there in the evenings and on weekends, and couldn't help but notice that the establishment was usually packed with customers. Suddenly he saw a way out of the utility company. He asked Brown to sell him the right to build a second restaurant, about 25 miles away, for $1,000. When Portillo couldn't get a business loan, Brown agreed to partner with him. Portillo and his wife opened their first store in Elmhurst in June 1958.

By handing out free samples and distributing homemade coupons, the Portillos slowly established a regular clientele. As the pace of sales at both stores increased steadily, employees started approaching Brown and Portillo about opening restaurants of their own. The two men opened five restaurants in partnership with them, retaining 52% ownership. Says Portillo: "I was a young, cocky, smart-alecky kid; he was old and wise. We were a great team." By 1963, Brown, who was 25 years older and spent winters in Florida, was letting Portillo handle day-to-day management. He offered advice when he thought Portillo needed it. "He would come back in the summer and raise hell," says Portillo, who was earning more than he'd ever imagined.

By 1965 the franchise boom had started. Friends, family, and investment groups besieged Portillo with requests to open their own locations. He began franchising, growing the chain to 100 stores by 1987. When some units failed to perform as well as Portillo expected, he got a $3 million loan to buy back 25 of them; he sold others. By that point, competition from chains like Kentucky Fried Chicken was intense. To gain an edge, Portillo began serving a family-sized portion of pasta with each meal, renaming the restaurants Brown's Chicken & Pasta in 1991. Then Brown passed away on Dec. 30, 1992. "It was a big loss," says Portillo. "He was a good ear. He had so much wisdom, so much common sense."

Portillo could have used Brown's help ten days later, when he received the most awful wakeup call of his life from the employee who first heard about the crime. Portillo arrived in Palatine and found a crowd of police and journalists swarming around the roped-off scene. As police sifted through the evidence, Portillo spent the weeks that followed attending funerals and praying with the victims' families. He would soon find out what was in store for him for years to come. The first person he visited was Emmanuel Castro, whose teenage son, Michael, had died. Palatine Mayor Rita Mullins joined him. "When she introduced me to him as the president of Brown's, he started hitting me in the chest," says Portillo. "I put him in a bear hug so he couldn't hit me. He started crying and shuddering and shaking, and his knees gave out. He said, 'I just want my Michael back.' I lost it," says Portillo. "I said, 'I don't know what I can do.' That was so traumatic. I've never experienced emotion like that. He lost the most precious thing in his life."

The tough-minded businessman who had always been able to overcome adversity through force of will suddenly felt powerless. After he got home from one funeral, "Whammo, it hit him," says Joan Portillo. "He couldn't stop crying no matter how much I held him." Worried, she called her son and a friend. The friend, who'd been alarmed by her tone, phoned the security guards at their gated community. They'd called the police, and an officer knocked on the door ten minutes later. Joan assured him that everything was all right. Then their son showed up and walked into the bedroom, where Portillo was sobbing. "He took his dad in his arms and held him," she says, choking back her own emotion. "Frank finally fell asleep."

He woke up to business problems that he'd never anticipated. TV news stations featured constant updates on the grisly crime, which had taken place around 9:10 p.m. on a Friday night in a busy shopping center. "We were on the morning, afternoon, and evening news for probably all of 1993," Portillo says. Customers stopped coming to Brown's; Portillo says sales dropped 20% by the end of 1993, effectively wiping out his profit. "If they had found the perpetrators shortly after the incident, it would have been so much better for the survival of the chain, but the franchisees were suffering; they couldn't pay their franchise royalties--it was a disaster," says David L. Epstein, an investment banker who, as principal of J.H. Chapman Group, stepped in to help Portillo manage the firm's finances. "I remember friends who would say, 'You know where that Brown's massacre occurred?' and give me an address that was nowhere near it."

As Brown's fell behind on its bills, Portillo's accountant and lawyer dropped him. His bank put him into "workout," selling stores to pay down his $3 million loan. Portillo liquidated other ones to raise cash, gradually paring down to 60 restaurants. In 1995, Emmanuel Castro sued Brown's, charging that the company hadn't done enough to keep employees safe; Evelyn Urgena, mother of Rico Solis, followed suit in 1996. A judge eventually decided in favor of Brown's, but Portillo was shocked that they had turned against him. Portillo considered selling his business. Though Epstein helped him win a $2 million loan, he still owed $4 million to his vendors. But bailing out would mean abandoning his franchisees, many of whom had invested everything in the restaurants. He decided to tough it out. "If we failed, they would fail and lose their life savings," he says.

Tormented by anxiety, Portillo often got out of bed at 3 a.m. and tried to clear his mind by exercising on his Universal Gym. Sometimes depression would overwhelm him during the day. "It's bad to see a man cry, but I would just break down," he says. "You...just felt like you were losing everything you and all your employees and franchisees worked so hard for." Haunted by the image of Emmanuel Castro's collapse, Portillo began speaking to groups of small-business owners in Chicago to encourage them to heighten security. As he struggled to understand how anyone could have committed the heinous acts at Palatine, he began researching the root causes of violent crime. When he contacted the Chicago Crime Commission for information, he learned that many convicts were functionally illiterate. He soon helped set up a committee to raise test scores at Bernard Moos Elementary School, located in a gang-ridden neighborhood of Chicago. He also donated a restaurant to Reach Out & Touch, a nonprofit that taught business skills to troubled young people.

But Portillo knew such efforts wouldn't bring the perpetrators to justice. In 1993, Robert Fuesel, a former investigator for the U.S. Treasury Department, invited Portillo to join the Chicago Crime Commission, of which he was executive director. Fuesel had heard about Portillo's lectures to local business groups on security, and he thought Portillo would be the ideal person to help him generate a small-business membership. Portillo decided to join. He began talking with members like Thomas Hampson, a private investigator with a law enforcement background, and John Flood, then president of the Combined Counties Police Association union, about whether more could be done to solve the case. Based on what they told him, he concluded that there should be more coordination with experienced homicide detectives in Chicago, and that a statewide task force should be set up to help small suburban police departments tackle major crimes. Portillo met with former Palatine police chief Jerry Bratcher, but when that failed to lead to the results he wanted to see, he persuaded the commission and the Better Government Association, which had once fought Al Capone, to investigate the case. "I don't think that man ever rested," says Richard Zuley, a veteran Chicago police detective who worked briefly with Palatine police. "He was truly driven to see that justice was done." The BGA released a report in 1997 that was deeply critical of the way the case had been handled. The report, for example, cited accounts by witnesses that the police allowed more than 50 people to enter the scene, leaving a large number of extraneous fingerprints. Palatine police declined comment, but a report by the Illinois State Crime Commission in 2000 defended them. Chief Bratcher, now retired, said the police did all they could, and that the BGA report was full of "innuendo, half-truths, and...outright lies."

For the next few years Portillo continued his crusade but began to slow down. Nine years after the tragedy, the Brown's Chicken & Pasta franchise at Smith Street and Northwest Highway in Palatine had long since been demolished. He began to wonder if the crime would ever be solved--until May 18, 2002. Portillo and his wife were sitting on the sofa in their condo, watching the evening news, when a picture of Brown's flashed across the screen. He didn't want to get his hopes up as he heard that two men had been arrested for the murders in Palatine. Police had investigated other suspects over the years, without any breakthroughs. This time, though, a grand jury indicted James Eric Degorski, 30, of Indianapolis, and Juan A. Luna Jr., 28. Luna had worked at the restaurant until a few months before the murders. Detectives had used DNA technology to connect Luna to a partially eaten chicken dinner found at the scene. The break in the case came in March. Degorski's ex-girlfriend, Anne Lockett, 27, told police that Degorski had confided that he and Luna were involved in the murders nearly ten years before, says her lawyer, Kenneth Goff. Goff said she was in an "abusive" relationship with Degorski and feared reprisal if she went to the police. Another woman also came forward in March, saying she picked up the suspects in her car after the murders. News reports said six others had known the identities of the alleged perpetrators but failed to tell the police.

Portillo, meanwhile, has kept a promise he made to Castro to create a safer workplace, installing security cameras at all his restaurants and sending out frequent reminders of the importance of strict safety measures to his franchisees and employees, even at the risk of increasing his company's legal liability. It was because Brown's had left security to its franchisees that a judge decided the company couldn't be found negligent when the parents of the two teenage victims sued it.

With Degorski and Luna awaiting trial with not-guilty pleas at press time, Portillo was concentrating his energy on growing Brown's Chicken & Pasta. He was moving forward on a plan to renovate his restaurants, roll out a new line of Chicago Way sandwiches, and expand a profitable catering sideline that he started in 1994. Epstein, the investment banker, believes that thanks to Portillo's determination, the chain, which last year posted sales of $33 million, could pull off a strong comeback. "His passion for his people and his concept have allowed this chain to survive through adversity," he says. "Other operators would have folded their tents and gone home. But not Frank."

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