Psychodramas like the new film “Hot Milk” require a degree of patience from viewers that often is in direct relation to their taste for charged imagery. From their directors, they frequently require smooth control of tonal shifts and a firm grasp of character to stabilize the emotion and storyline, with the best of them — think Ingmar Bergman’s “Persona” or Peter Jackson’s “Beautiful Creatures” — maintaining a steady hand while exploring acute psychological breakdown. 

Unfortunately, “Hot Milk” is not on the same level as those films, though its story of a 20-something daughter taking care of her disabled mother does shimmer with an edgy energy, at least initially. What stands out the most are its performances, especially that of the young lead, Emma Mackey as Sofia, who more than holds her own beside an Irish acting titan, Fiona Shaw, as mother Rose. Also strong is a Luxembourgish-German actress, Vicky Krieps, as Sofia’s free-spirited summer love Ingrid.

The narrative starts as Sofia and her mother begin their stay somewhere on the coast of Spain. The pair are not there for leisure; Rose is wheelchair-bound and is enlisting the help of an unorthodox doctor to get her mobile again. At the first appointment, the matriarch explains how she stopped walking when Sofia was 4 years old, which we later learn coincided with her Greek ex-husband’s abandonment. 

Her inability to walk presents a strange case from a clinical standpoint, considering that once a year she is able to walk. Surmising that despite her complaint of pain the cause may be psychosomatic, Dr. Gomez (a slightly, knowingly ridiculous Vincent Perez) questions Rose about her family when she was younger. During their second consultation, he even asks her to draw up a list of her enemies.

Back at their seaside rental, the setting is anything but tranquil, with the power regularly going out, a nearby dog barking day and night, and mosquitoes flitting about. The relationship between mother and daughter, too, is tense, with Sofia balancing patience and affection with barely concealed bitterness at having to be a caregiver. Studying anthropology, Sofia is dismissed as a “permanent student” by her demanding, persnickety, and self-centered mother.  

Despite the beachy atmosphere, many of the film’s images at this stage have an eerie, intentionally artless quality to them, particularly interstitial shots such as a barbecue left unattended and a desolate, defunct factory near the shoreline. Soon, though, the story and its direction by first-time filmmaker Rebecca Lenkiewicz become both heady and sloppy. 

Sofia sees Ingrid for the first time while the latter is on horseback, like a hero in a fairytale, and then is subsequently stung by a jellyfish, foretelling danger by association. Symbolism increasingly floats in amongst the proceedings, while inconsistencies, non sequitur dialogue, and abrupt editing make for a moviegoing experience that feels overheated and off. Basically, “Hot Milk” turns into a “hot mess.”

Ms. Mackey shoulders the weight of the film’s clunkiness and kooky seriousness confidently, anchoring its themes with her passionate gaze and emotional acuity, particularly in scenes in which her character has outbursts. The actress’s angular face also complements Ms. Krieps’s equally sculptural visage, and the palpable attraction and natural intimacy between them almost transforms the movie into a love story. 

The narrative’s main interest, though, lies with mother-daughter dynamics, and Ms. Shaw portrays a parent whose controlling, needling ways drive her daughter to obsessive behavior and even violence. Whether Rose’s disorder is performative or genuine is unclear, yet the character’s limited physicality does not restrict the actress’s expressive use of her arms, hands, and neck. When her big family secret is revealed twice, in a late scene with Dr. Gomez and again during the climactic one with Sofia, details remain sketchy, yet Ms. Shaw’s portrayal of a woman in denial burns with poignancy. 

Ingrid carries a secret as well, aligning her internal struggle with Rose’s, and yet Sofia’s two key relationships seem to exist in vacuums, with her lover and her mother each barely acknowledging the other. One wonders if this and the film’s facile symbolism are also part of the acclaimed novel by Deborah Levy on which it was based. 

As a cauldron of trauma, avoidance coping, and promiscuous summer sexuality, “Hot Milk” does mix in a few emotional and psychic points. It leaves one, though, wanting to deal with its various abstractions and inanities not by speaking with an analyst, but by taking a cleansing cold shower.