How does a romance go from “Before Sunset” to “Blue Valentine?” Argyris Papadimitropoulos charts the dissolution of a passionate fling into domestic resentment in “Monday,” a film that succeeds at capturing the peaks and valleys of a relationship but sputters out when capturing the mundane moments in between. Not unlike the on-screen pair, Mickey (Sebastian Stan) and Chloe (Denise Gough), Papadimitropoulos excels in exploring the couple’s carnal journey but can never quite hit a groove when it comes to finding stability in their cohabitation.

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The film’s best stretch comes in the first thirty minutes, a dizzying and propulsive recounting of their relationship’s infancy. The two American expats meet at a disco club in Athens: Chloe is a freelancing immigration lawyer heading back stateside after 18 months; Mickey, a DJ living comfortably and care-free in his seventh Grecian year. His friend connects the two on the dance floor, and their libidinous energy grabs attention as quickly as Papadimitropoulos’ impressive opening tracking shot. Chloe and Mickey go from first conversation to first kiss to waking up naked together on a beach in rapid succession, even by cinematic standards.

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“Monday” then takes its time luxuriating in Mickey and Chloe’s tentative advances as they try to feel each other out. Is the connection purely sexual, or is there the potential for something sentimental? Neither can quite get a firm read on the situation, but at the slightest hint of pulling away, one draws the other back in. At his best, Papadimitropoulos recalls the observational bliss of Barry Jenkins’ tender debut feature “Medicine for Melancholy” as he lets two lovers explore what their relationship might mean through conversation.

Unfortunately, “Monday” is not a short film. It continues on after the initial courtship and never quite regains the solid footing of its first act. As Mickey and Chloe commit to living together and begin to suffer the growing pains of a relationship, the film grows increasingly leaden as acrimony blossoms between them. Other filmmakers have managed to wring compelling drama out of a couple’s enmity, but all Papadimitropoulos’ attempts fall flat.

The film suffers from Mickey and Chloe lurking in a murky middle ground: neither broad enough to function as archetypes nor defined enough to captivate as characters. Gough, a talented utility player in films such as “Colette” and “The Other Lamb,” catches the better break thanks to Chloe facing more turmoil in her personal and professional life. She’s skilled at conveying the waves of turmoil and doubt roiling under her placid exterior, although these emotions rarely break through to the milquetoast Mickey.

Sebastian Stan is an actor of considerable charisma, so it’s easy enough to understand how Chloe gets attracted to Mickey’s magnetism in the puppy love stage of their relationship. The man wears socks adorned with Botticelli’s “The Birth of Venus,” for heaven’s sake! But Stan’s power is not so overwhelming that he can coast on star image alone or cash in on the currency of past romantic roles. He needs guidance and direction to allow that potent force to animate a character, and that’s largely missing in “Monday.” Particularly once Mickey enters his mopey sad boy phase, it becomes difficult to understand what keeps Chloe so invested in making their partnership work.

Mickey is not just some god of sex, either, casting a powerful sensual spell over Chloe with his prowess. She initiates contact just as frequently as he does, which keeps “Monday” consistently horny from start to finish. (There’s a much more sexist version of this premise that would make an ambitious woman give up her career for an attractive DJ, and thankfully the film steers far clear of that trope.) Papadimitropoulos shows the marked evolution of their erotic connection from passionate to commonplace to desperate. Yet by the time Mickey declares that they both used each other throughout the relationship over a borderline animalistic hookup, it has become clear that the film has lost the connection between the form of their sexuality and the emotional stakes it represents for the two characters. [C+]

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