The newest 'Simpsons' character is a hypnotherapist breast cancer survivor with 'uniboob.' Here's her inspiring backstory.

An episode of beloved comedy The Simpsons is about to get serious about breast cancer awareness.

In a groundbreaking moment for survivor visibility — specifically of women who have undergone mastectomies and opted to stay flat rather than choose breast reconstruction surgeries — the Oct. 24 episode introduces the character Dr. Wendy Sage, aka Sage. She's a hypnotherapist who has had a unilateral mastectomy, leaving her with what fellow survivors endearingly refer to as "uniboob."

Sage is the brainchild of Los Angeles–based actress, writer, breast cancer survivor and flat advocate Renee Ridgeley, who also voices the character, and who says that while Sage's role is small, it's "crucial," as she's the person Marge and Lisa meet with in order to work out some issues relating to body positivity. Ridgeley, who has many connections in the entertainment industry, has been "hounding different people," she says, "one of them being my husband," Matt Selman, who is The Simpsons showrunner. "I was like, 'Let's get a breast cancer survivor on The Simpsons!'"

Selman, who says he has found his wife's turn to advocacy work both "inspiring" and "hopeful," was all for it, he tells Yahoo Life — and in fact lived for more than a couple of years with an index card on his desk that said, "Simpsons uniboob" (because a doubly-flat look wouldn't visually translate in animation, Ridgeley explains). But he wanted the character's introduction to happen organically.

"We are always looking to reflect the world as the world changes for good and for bad — usually bad! — but we didn't want it to feel preachy or jammed in. We wanted the fit to feel really clean," Selman says. "Viewers are very sensitive to feeling like they’re being lectured to."

So it was "kismet," the longtime show writer continued, when they started working on a new episode written by Juliet Kaufman, which had a theme of body acceptance. "This is, like, the perfect episode [for Sage]," he says. "It's like a grace note."

Ridgeley explains that the new character functions not as an advocate for any specific medical choices or causes or organizations, but as someone simply living her life, just with a uniboob.

"While Sage has all the telltale signs of a breast cancer survivor: a visible scar from a port-o-cath (a device used to deliver chemotherapy), curly hair regrowing from chemo treatment, an obviously one-breasted appearance, and is visually concave on her mastectomy side, the episode does not focus on her past disease," she notes. "Sage shows up as exactly who she is now. By living openly as a one-breasted woman, she sends a message of acceptance and wholeness celebrated by individuals in marginalized groups."

The episode, she tells Yahoo Life, is "very emotional."

Ridgeley, who received her breast cancer diagnosis in 2016, at first chose reconstruction, only to have her implants cause various health issues which prompted her to get them removed. Sharing her story in a Washington Post op-ed was the start of her flat-advocacy work. She’s since run support groups; founded the Less Than Two Breasts advocacy campaign and Instagram page; cofounded Stand Tall AFC, the flat-visibility campaign for October's Breast Cancer Awareness month, with Flat Retreat; and participated in Flat Retreats, including last weekend in New York City to coincide with the Making Strides for Breast Cancer walk.

There, Stand Tall team members wore shirts and held signs bearing an image of Sage, and offered cards that said "#iamsage" on one side had a scannable code leading to "going flat" resources on the other side.

"I think that the flat community is just blowing up, and everybody seems to be contributing in the way they can," Ridgeley told Yahoo Life while taking part in the walk. "It started in the '70s with Audre Lorde, and here we are now."

In 1980, Lorde, who had undergone a unilateral mastectomy, published The Cancer Journals, responding in it to what had been criticism over her choice to never hide or pad her missing breast with a prosthetic. She compared the situation to that of Moishe Dayan, the prime minister of Israel at the time, who wore an eye patch, noting that "nobody tells him to go get a glass eye," and that he is instead viewed as "a warrior."

Lorde continued, "Well, women with breast cancer are warriors, also. I have been to war, and still am. So has every woman who had had one or both breasts amputated because of the cancer that is becoming the primary physical scourge of our time. For me, my scars are an honorable reminder that I may be a casualty in the cosmic war against radiation, animal fat, air pollution, McDonald’s hamburgers and Red Dye No. 2, but the fight is still going on, and I am still a part of it."

And now, so is Sage, whose Sunday premiere is welcome news to many survivors, including Jenny Beaupre of Illinois, who opted for a unilateral mastectomy without reconstruction when she was diagnosed with breast cancer at the start of the pandemic, and who shared about that decision on Instagram last year.

"Finally, a representation for uniboobers!" she tells Yahoo Life upon learning of the new Simpsons character. "It's awesome that the creators of this show understand the harsh reality of what people like me go through, but are giving it deserving humor it needs. I love the shock factor of walking into anywhere with a tight shirt and am like, 'Yep, that's ol' boob. My eyes are up here though.'"

There is plenty of humor surrounding all the characters in the episode, including Sage, who is not only the carrier of an important message about self-love but "is silly, too," promises Selman.

But that's balanced with poignancy.

"The people who have watched it so far are more emotionally touched by any other episode I've ever worked on, which is just complete magic," says Selman, who has been a writer and producer on the show since 1998. "I did feel good about it. But people are just watching it and crying! You do want to make them laugh," he notes. "But crying is a close second."

Watch Sage's premier on The Simpsons, airing Sunday on Fox at 8 EST/7 CST.

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