Tony Gilroy has built a sturdy career as the director of the Bourne films and show runner of the popular Star Wars spin-off Andor. He directed Tilda Swinton all the way to an Oscar for her remarkable performance in the legal potboiler Michael Clayton.

As the first feature film he has directed since 2012’s The Bourne Legacy, the classical music drama Behemoth! promised to be an intriguing return from a master of threading the needle between slick action and deeply felt drama. His new film comes with a score from nine A-list composers who have banded together and called themselves The Behemoth! Collective, a stacked cast and a womanizing central character who looks phenomenal in a tux: “Tár for straight men”, as a friend of mine put it.

If only Pedro Pascal had an iota of Cate Blanchett’s charisma or Gilroy came close to Todd Field’s elegant braiding of genres. Our protagonist is Alex (Pascal), an inscrutable cello maestro who has moved home to Los Angeles after nearly two decades on the road. The city offers him regular, if soulless, session work scoring TV shows and movies, as well as the opportunity to be closer to his brother (Will Arnett) and mother, a respected harpist who is suffering from ill health.

Alex is haunted by memories of Nadia (Eva Victor), a violinist who he had a brief, passionate affair with six years ago. “You’re a monster,” she tells him approvingly in a flashback to the night after their first performance together. “Really fucking good”. The sex is out of this world, and their fights are just as passionate. After Nadia’s death, Alex becomes obsessed with her daughter (Alexa Swinton, a distant cousin of Tilda), a musical prodigy at just 15 years old, and wonders if he could be her father.

That all could be intriguing, but Behemoth! is fatally undone by a disorienting Russian doll-like structure with timeline leaps that serve little purpose other than proving how many Gillian Flynn paperbacks the film-makers might have read. The film never quite comes together, giving it an overwhelming sense of aimlessness as we move from one inconsequential subplot to another. Alex’s friendship with a teenage cellist (newcomer Kaya Ralls) is sweet but undercooked and his relationship with his brother has the emotional depth of a fist-bump. Tonally, Behemoth! is all over the place, flitting from bittersweet yearning to grief drama to Deadpool-esque action scenes: in one, Pascal’s character is chased through a mansion’s grounds by a terrifying pack of … cuddly corgis.

Both whiplash-inducing and ponderous, Behemoth! doesn’t make you feel much of anything at all despite its weighty themes. About halfway through the film, we discover that Alex is a former child prodigy who performed on the Johnny Carson show at six years old, and in another bizarre scene he tells a lover that he lost his virginity at age 13 to a vocal arranger who subsequently had sex with his dad. These are the kind of experiences that you could spend a lifetime in therapy unpacking, but Gilroy lurches so quickly from one disorienting flashback to another that they barely have a chance to register.

Neither does the film seem to know what to do with the women currently in Alex’s life. Olivia Wilde has a scenery-chewing role as his tempestuous current love interest, but save for a bizarre moment in the third act, her character seems to exist only to scream at him and look fierce. Victor, the breakout Sorry, Baby star, is pyrotechnic. I missed her whenever she was not on screen, which is about 95% of the movie.

Pascal is a frustratingly insubstantial anchor to the film. For all his virtuosic musical skills, Alex feels like a distant spectator to his own life, and “the kind of guy that stuff just happens to” doesn’t make for a particularly engaging watch. At times, I wondered whether Alex’s sleepy meanderings were some kind of conceptual statement about the numbing effects of grief or whether a perpetually furrowed brow is simply Pascal’s style of acting. A plot-free character study requires the sure hand of, say, a director like Kelly Reichardt or Mia Hansen-Løve. Gilroy’s film doesn’t have the juice to pull it off.

• Behemoth! is screening at the New York film festival and is released in Australia on 3 December and in the US and UK on 4 December