Few doctors have made more money in the weight-loss business than Beverly Hills brothers, Julian and Michael Omidi.
The brothers, who once were featured in the cable program "Dr. 90210," are the men behind a heavily advertised Southern California business called 1-800-GetThin and affiliated surgery clinics that have made millions of dollars offering an outpatient procedure that constricts the stomach with what's called a "Lap-Band."
Done right, the Lap-Band procedure is a safe technique. But a "20/20" investigation that will also be featured on "World News with Diane Sawyer" has found that in the past three years, five patients have died after Lap-Band surgery at the brothers' California clinics.
Watch the full story on "Losing It: The Big Fat Trap" on "20/20" at 10 p.m. ET.
Thousands of people signed up for Lap-Band surgery at the Omidis' clinics after hearing ads that said, "Let your new life begin, call 1-800 Get-Thin."
Among them was Cassie Gibbons, who lost more than 100 pounds and became the poster girl for 1-800-Get-Thin, appearing in advertisements showing her svelte new shape. "I've tried every diet out there," she says in a commercial. "The Lap-Band was the easiest thing I've ever done."
"I just wanted to get thin," Gibbons told ABC News. "I wanted my new life to begin, to get thin."
But some patients died not long after undergoing surgery. John Faitro says his wife Laura died after doctors lacerated her liver during the procedure but sent her home without revealing the mistake.
"She wanted to feel good," said John. "They made it seem so easy."
John, who is blind and now left without anyone to care for him, says his wife was sent home from the clinic in great pain.
"We just thought it was a normal operation, because she was in pain ever since she left," said John.
The clinic's lawyers say Laura Faitro had other health issues, that the lacerated liver was not the cause of her death, and that they are deeply upset about the death.
'Don't Worry, We Make $21 Million A Month'
But the doctor who operated on Laura Faitro testified that one of the Omidi brothers, Julian, told him they made too much money to worry about the death or the cost of a lawsuit.
During a deposition in a lawsuit filed by John Faitro, Dr. Ihsan Shamaan testified that Julian Omidi said that if Shamaan had killed her, "that means there would be a lawsuit."
"Julian Omidi's response to me was, 'Don't worry, we make $21 million a month, one million is okay,'" said Dr. Shamaan.
The Omidis say the doctor is lying, but John Faitro says he believes the doctor, not Julian Omidi.
"He has a love for money," Faitro told ABC News. "He took a lot away from me."
The Omidis don't do any of the actual surgeries themselves. Julian Omidi had his medical license revoked by the state Medical Board for dishonesty, citing his involvement in the burglary of exam papers when he was in college.
Michael Omidi had been put on probation as a doctor for three years, and was reinstated in 2011.
"There were allegations of gross negligence," said Los Angeles Times columnist Michael Hiltzik, who has written extensively about the Omidis.
A series of articles and columns in the paper first revealed the deaths and despite being hit by a string of lawsuits from the Omidis, its reporters continued to raise questions about the marketing pitch to overweight Californians.
Said Hiltzik, "What [patients] need is good medical care, and qualified medical care, not medical care that they can get off a billboard."
Dyanne Deuel headed the medical support staff at one of the Omidi clinics until, she said, she quit in disgust.
"I've never seen in my life standards so below the average of what they should be," said Deuel. "They would run the patients through. They would send patients home that were complaining of shortness of breath and many other issues. [Patients would be] in severe pain, and they would push them out the door. 'I'm sorry, we need the bed. You need to go.' "
Deuel is now suing the Omidis, who claim she is making things up to help her lawsuit.
Homicide Investigation After Surgery Death
The Omidi brothers came under fresh scrutiny when Paula Rojeski became the fifth person in the past three years to die after 1-800-Get-Thin Lap-Band surgery. Her death, in September 2011, attracted the attention of Los Angeles homicide detectives.
Rojeski's friends say she wanted to lose weight for an upcoming birthday.
Recalled friend Marni Rader, "She said, 'Oh, I want to get this surgery.' And I said, you know, 'Why Paula, you don't need it. You look great, you are fine.' [She said,] 'No, no, I want to be skinny, I want to be skinny.' "
Paula died on the operating table, and the circumstances of how that happened -- and whether she could have been saved – have now led LAPD homicide detectives to investigate whether a crime was committed.
Lawyers for some of the other families suing the Omidis say they also have been contacted for more information by a number of law enforcement agencies.
"This place seems to be a magnet for bad outcomes," said Alex Robertson, an attorney for the families. "Ultimately, justice may be for these families that if laws have been broken, people responsible go to jail, that they get shut down, that doctors lose their license. This can't continue."
Said John Walker, another attorney for the families, "There doesn't need to be another name on that death lists. It needs to get stopped."
The Omidi brothers say there are greater risks with obese patients and that their clinics are professionally accredited and meet the highest standards. But they declined repeated requests from '20/20' for interviews.
And now even their own poster girl, Cassie Gibbons, has turned on them, saying she fears she may have been responsible for recruiting some of those patients who died.
"If any of those families lost someone because of me," she said, "my apologies are from the bottom of my heart, because I would never want anyone to lose anyone over this."