Julianne Moore in Todd Haynes’s “Safe.” Courtesy of Sony Pictures Classics.

Throughout her extraordinary career, Julianne Moore has often excelled at playing characters who are ostracized. Consider her 1950s housewife who develops forbidden feelings for her black neighbor in “Far from Heaven,” or her vice-presidential candidate hopelessly adrift in a political realm beyond her comprehension in “Game Change,” or her self-loathing drug addict who feels as if the entire world is conspiring against her in “Magnolia.” Yet it is the alienation caused by illness—both physical and mental—that has inspired Moore’s most potent and devastating work to date.

To her surprise, Moore is currently the Oscar front-runner for Best Actress this year, thanks to her deeply moving portrayal of a linguistics professor diagnosed with early-onset Alzheimer’s in Richard Glatzer and Wash Westmoreland’s “Still Alice.” When I spoke to her at the Gotham Awards this past December, Moore displayed an unbridled giddiness at the very notion of her film being a part of the awards season conversation. “This is a movie that we made for four million dollars last March, it was mixed in August and got a distributor in September,” Moore said. “We can’t even believe that we’re out.” She also noted how the film was a personal labor of love for its directing duo. “They are a couple and have been together for a really long time,” Moore said. “Richard has ALS, so they are facing their own issues of mortality.”

Perhaps it was that knowledge of the filmmakers’ behind-the-scenes struggles that made “Still Alice” such a poignant experience for me. The film has been criticized for some of its Lifetime-style tropes, and I agree that the tinkling piano score and close-ups of teary-eyed extras are rendered all the more distracting and unnecessary by the authenticity of the performances. If Moore wins the Oscar, she’ll be the latest in a string of veteran actresses honored by the Academy for work that single-handedly bolstered the impact of their respective pictures. Think Kate Winslet in “The Reader,” Meryl Streep in “The Iron Lady” or Cate Blanchett in “Blue Jasmine.” Like “Alice,” “Jasmine” also cast Alec Baldwin as an increasingly distant husband, though it’s a pleasant surprise to see pangs of vulnerability fracture the actor’s typically slick persona in his scenes with Moore.

It’s equally wonderful to watch a post-“Twilight” Kristen Stewart (star of the franchise Moore memorably ridiculed in “Crazy, Stupid, Love.”) exude a revitalized glow as Alice’s youngest daughter, Lydia, an aspiring actress long misunderstood by her mother. Glatzer and Westmoreland’s script, based on Lisa Genova’s novel, will be chock-full of moments instantly recognizable to anyone who has ever been afflicted with an illness or has ever cared for an ailing loved one. Lydia’s frustration toward Alice (“You can’t use your situation to get your way!”) eventually crumbles as she gains a greater awareness of her mother’s decline, eventually emerging as her most devoted caregiver.

Oscar prognosticators are favoring Moore in part because of her nearly three-decade-long legacy of acclaimed work that has previously earned four Academy Award nominations. What struck me while watching “Still Alice” was how it contrasted in intriguing ways with Todd Haynes’s masterpiece, “Safe,” another Sony Pictures Classics release that will celebrate its twentieth anniversary this year and just might be the finest screen showcase of Moore’s career. She plays Carol, a self-described homemaker who contracts an insidious autoimmune illness, dubbed “multiple chemical sensitivity” (MCS), that makes life in 20th century suburbia utterly impossible. She develops inexplicable allergies that trigger unsettling symptoms, much to the chagrin of her husband and the bafflement of her doctor.

The film’s second half finds Carol seeking treatment at the isolated health retreat, Wrenwood, presided over by Dr. Dunning (Peter Friedman, foreshadowing Philip Seymour Hoffman’s Lancaster Dodd in “The Master”), a fascistic manipulator who instills participants with a sense of guilt, causing them to believe that they have made themselves sick. It’s here where the film’s AIDS metaphor is most apparent. In his excellent audio commentary track with Moore, Haynes discusses how both MCS and AIDS cause victims to lose their identity along with their immunity (how fitting that Lydia chooses to comfort Alice by reading a passage from “Angels in America,” Tony Kushner’s landmark play on the AIDS epidemic).

Yet whereas Alice starts out with a strong, fully formed identity molded by her formidable intellect and flourishing family life, Carol’s life is tragically empty. Though she initially cites stress as a probable cause for her ailments, the only tangible “stress” that enters her uneventful days materializes in the form of wrongly delivered furniture. There’s a great darkly comic beat that occurs when Carol gravely utters, “Oh my god,” and the camera pans to the left, revealing not a dead body but a couch clashing aesthetically with her gleaming decor. Haynes had admitted that Kubrick served as a key influence, and the late master’s fingerprints can be witnessed throughout the film’s sterile suburban environments replete with an ominous, ever-present ambience suggesting the gradual snuffing out of humanity.

“Safe” is as intensely uncomfortable as “Still Alice” is palatable to the mainstream, right from the opening scene of Carol enduring a session of passionless lovemaking with her husband before planting a chaste kiss on his cheek. She is entirely disconnected from her life long before her illness strikes—even her stepson coldly treats her like an unwelcome stranger. “She doesn’t want to be in anyone’s way,” Moore explains in the commentary. “I tried to keep my voice unconnected to my body by talking above my vocal chords, which gave it a breathy, bodiless quality.” This persona couldn’t be further removed from the conviction that Alice maintains at work and home even as her memory starts to flicker away.

The topic of “love” is mentioned at length in both films, yet only “Alice” contains any actual traces of it. When she says the word late in the film, she affirms the fundamental clarity of feeling that remains in her mind even after everything else has gone out of focus. When Carol says, “I love you,” to her reflection in the profoundly haunting final shot of “Safe,” she’s simply regurgitating words with little understanding of their meaning. One suspects that Carol has never truly experienced love, and therefore has no clue of how to love herself, resigning to live a life of superficial contentment devoid of emotional intimacy. An especially frightening moment occurs when Carol sports glimmers of Alzheimer’s, suddenly forgetting who and where she is while sitting in bed. Both “Safe” and “Still Alice” convey the primal horror of a bleak diagnosis resulting in one’s own imprisonment. Carol ends up imprisoned in a “safe room” cut off from all human contact—in essence, a spacious coffin—while Alice is imprisoned in her body.

If “Still Alice” registers as a more hopeful film, it’s because its heroine opts to accept the reality of her situation and make the best of her remaining days. Alice states this in a stirring speech she delivers to a visibly moved crowd, while running a highlighter along each line to prevent her from losing her place. It’s a moment of personal triumph for Alice, and Moore makes it genuinely inspirational. Carol also has a speech toward the end of “Safe,” that she delivers during a surprise birthday celebration at Wrenwood. Her words are as rambling and incoherent as Alice’s are eloquent, grasping onto disjointed ideas spewed by the clinic’s patronizing gurus and hurling them back in their faces, causing them to momentarily stew in a squirm-inducing silence. To me, this is Carol’s moment of unintentional triumph, exposing the futility of her surrounding cult-members’ misguided efforts and their Sarah Palin-esque lack of real answers. The fact that every line of the scripted, sublimely performed monologue sounds entirely improvised is a testament to Moore’s enduring genius.

“Safe” is available on Blu-ray and DVD, courtesy of The Criterion Collection. “Still Alice” is currently playing in theaters.