The National Institute of General Medical Sciences (NIGMS) defines a biological clock as an organism’s “natural timing” device—present in “[…] nearly every tissue and organ”—that regulates the daily cycle of “physical, mental, and behavioral changes.” However, the cycle—known formally in NIGMS’ text as a circadian rhythm—isn’t how many people define the phrase. “Clock,” writer and director Alexis Jacknow‘s debut horror feature, ambitiously attempts to explain how the term is used daily and who it affects the most. 

Writing for The Washington Post, assistant tech editor Lisa Bonos—who previously wrote editorials on dating and relationships—stated, “The term is usually applied to women.” Jacknow’s primary subject is one such woman: Ella Patel (Dianna Agron; “Shiva Baby,” 2020), a successful interior designer with everything. Her professional life thrives, and her husband Aidan (Jay Ali; NBC’s “Magnum PI,” 2018-2024) is madly in love with her. Her life seems perfect, except—according to her father, acquaintances, and immediate society at large—for one thing: the couple hasn’t had a baby yet.

“My parents gave me a dollhouse when I was 5, and I filled it with dogs,” photographer, documentary filmmaker, and conservationist Marcy Mendelson told journalist Mary Katharine Tramontana for The New York Times. “I obviously didn’t want kids,” she continued, “but I kept waiting to want them.” 

In Jacknow’s film, Ella is in a similar conundrum.

“Unfortunately,” her gynecologist, Dr. Webber, tells her during a routine checkup, hinting that her age technically makes her a geriatric, “you don’t get to be ‘not quite ready yet’ [to start a family] anymore.” Ella shows a moment of vulnerability toward the doctor and admits she doesn’t want to have kids, adding that she keeps waiting for her ‘clock’ to start ticking, but it hasn’t happened yet. 

Dr. Webber’s response is oddly chilling: “All women have a biological clock. Maybe yours is just broken.”

The problem? She’s not referring to the circadian rhythm but the current societal definition of the phrase, first coopted by columnist Richard Cohen—a man—for The Post. “Sometimes [she’s] married. Sometimes she’s not. Sometimes, horribly, there is no man on the horizon. What there is, always, though, is a feeling that the clock is ticking,” the columnist wrote in 1978 for an article called “The Clock is Ticking for the Career Woman.” Almost 40 years later, he would tell Bonos, “It’s just a biological fact. I didn’t invent it.”

Cohen may not have invented the scientific definition of a “biological clock,” but—according to author Moira Weigel for her book Labor of Love—he was the first to invent the “idea” of the ticking clock. Jacknow’s film tackles the very idea using the most effective way to externalize the anxieties that come from the pressure of having kids against the desire to be childfree: horror.

In a narrative device that feels right at home with “Ex Machina” and “A Cure for Wellness,” Ella is recommended to sign up as a test subject for a cutting-edge biotech facility to give “fixing” her biological clock a chance. Thus far, there are only a few jump-scares, but it’s all mostly played like a drama. The moment she steps in and meets Dr. Elizabeth Simmons (Melora Hardin; NBC’s “The Office,” 2005-2013), things suddenly feel very wrong. It’s a slippery slope to an endless rabbit hole that can’t lead her anywhere safe, and Ella’s forced to trust herself to navigate her way out of her brand-new nightmare.

This is where Jacknow introduces tokophobia—the irrational and pathological fear of pregnancy—and shifts gears to minimizing chronic physical pain in women, explicitly shown in the multiple therapy sessions between Ella and Dr. Simmons. Ella, who expresses extreme discomfort with the idea of going through the possible complications arising from pregnancy, is almost close to pooh-poohed by the doctor.

Freelance contributor Laura Kiesel, in her article for Harvard Health Publishing, titled Women in Pain: Disparities in Experience and Treatment, wrote that most studies on pain “[…] have focused on men,” pointing to a Marie Claire piece by Kayla Wesley Adler. Titled Women Are Dying Because Doctors Treat Us Like Men, Adler’s essay collates an exhaustive amount of research and lived experiences to prove her case that medical studies for many diseases are based solely on the understanding of male physiology at the cost of the lives of women.

While “Clock“ doesn’t really explore the specifics of this problem, its writer-director makes sure to weave into the narrative the innate fear and anxiety women could have, either to conform to social comfort or in anticipation of their concerns falling on deaf ears. Post her time as the test subject, Ella’s quality of life degrades massively—and we’re given the front-row seat to what she sees and feels, thanks to the in-universe verisimilitude via the fantastic color grading and editing, and Stephen Lukach’s (“Wrong Turn,” 2021) unsettling score.

Agron, Ali, and Hardin are excellent in their respective roles. Ali’s turn as an understanding husband isn’t in the film for much, but his chemistry with Agron shines and helps viewers empathize with him. Hardin plays probably the most incredible character in the movie: you’re never sure of her intentions, and while her demeanor seems safe and comforting, Martim Vian’s occasional framing choice can throw you off a little (in the best of ways, of course) and make you wonder if she can be trusted.

The film seems the bumpiest in its final act. While the director is perfectly attuned to the rising crescendo of tension in her narrative, the lack of revelation of many basic setups betrays her ambitious concept. It doesn’t completely derail the movie-watching experience, but it certainly makes the tail-end of the journey less satisfying than it should be.

At 91 minutes, Jacknow paces “Clock” perfectly enough for viewers to be thoroughly involved and terrified by proxy in the proceedings. Her handling of tone, style, narrative, and character writing feels accomplished, which makes the lack of proper payoff for some of its setups in the third act all the more frustrating. Thankfully, if the rest of the film is any indication, Jacknow’s a director with an exciting future and a talent to watch out for.