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.