Harry Connick Jr., <i>Living Proof</i> Harry Connick Jr., Living Proof

Strong women battling breast cancer. A sympathetic hero fighting for a cure. An ensemble of gifted actresses and a sexy charmer as their white knight. A three-hankie script and a four-hankie ending. Living Proof (Saturday, Oct. 18 at 9 pm/ET) might be Lifetime's most Lifetime-y movie ever. And yet the inspiring story, based on pioneering oncologist Dennis Slamon's dogged pursuit for a cure, took seven years to get to the screen — a struggle nearly as hard-fought as Slamon's battle to take his breast-cancer drug, Herceptin, to patients. "Dennis Slamon became a hero to me," says scriptwriter Vivienne Radkoff, who had read Robert Bazell's 1998 book Her-2, chronicling Slamon's efforts to get Herceptin on the market. "I was obsessed, but something would always stop the project." One interested producer had to drop out after being diagnosed with breast cancer herself.

Eventually, Radkoff's script would find some big-name champions — producers Craig Zadan and Neil Meron (Chicago, A Raisin in the Sun), actress (turned producer) Renée Zellweger and playing Slamon, singer-actor Harry Connick Jr. "No one would make Vivienne's movie," Zadan says. "She brought the story to us, hoping that we could somehow force it through the system. We've done a lot of dramatic shows that we care about, but this seemed to be the most important of all."

Connick, who was only 13 when he lost his mother to cancer, was similarly intrigued when offered the chance to play the pioneering doctor. "Playing Dr. Slamon brought me to places I hadn't been before as an actor," says Connick, whose acting jobs have veered mostly toward romantic comedy and stage musicals. Connick was filming the comedy Chilled in Miami (set for release in January) with Zellweger when he learned of the project. "Renée said that she was producing something I might like. I read the script and responded very well to the character of Dr. Slamon.

"The real Slamon was no stranger to the benefits of Hollywood connections. In 1981, he had successfully treated NBC Entertainment chief Brandon Tartikoff for Hodgkin's lymphoma, and later, Tartikoff's grateful wife Lilly volunteered to spearhead a multimillion-dollar fund-raising drive to finance clinical studies of Slamon's controversial cancer drug. Slamon's subsequent clashes with bureaucrats and skeptics, chronicled in Bazell's book and Radkoff's script, grabbed the interest of Meron and Zadan, and the producers recruited Zellweger (who'd starred in their Chicago) as an executive producer. The actress had a personal reason for signing on. "This story is about the research that saved the life of one of my best friends," Zellweger says, referring to Hollywood publicist and cancer survivor Nanci Ryder. "I feel great personal gratitude to Dr. Slamon."

With a green-light (but a small budget) from Lifetime, Meron and Zadan reached out to other friends. "We told them we don't have any money, we're shooting in three weeks in New Orleans, and there's no time to send you the script," Zadan says. The bare-bones invitation worked, drawing a distinguished cast that includes Angie Harmon, Amanda Bynes, Jennifer Coolidge, Regina King, Swoosie Kurtz, Trudie Styler and Bernadette Peters.

"I had never heard of this drug before," says Peters, who plays Barbara Bradfield, an early Herceptin success story. "This movie is going to make people aware of the drug, and aware that women have options out there. I'm just so proud to be in it."

Peters recently attended a New York City luncheon promoting the movie (and National Breast Cancer Awareness Month), mingling with costars as well as special guest Slamon. Currently developing ovarian-cancer treatments and continuing his breast-cancer research, the oncologist praised the film—particularly its power to raise awareness — and his portrayer. "Harry captured my frustration and frenetic behavior pretty well," he told TV Guide. "But he was much, much nicer."

Also at the event was survivor Bradfield. "The message of Living Proof," she said, "is that the diagnosis of cancer doesn't have to mean the end. You can have a life. Dennis is responsible for my getting old."