The classic whodunit is a tale as old as time: A rich billionaire is mysteriously murdered after his will is discovered, and the primary suspect is his grieving trophy wife. An eccentric detective swoops in to determine whether the police have identified the true culprit — or have been led dangerously astray.

This is the premise of “Diamond,” which follows detective Joe Diamond (Andy Garcia) as he uncovers the truth behind Randall Cobbs’ (Joe Drago) murder. Randall’s wife, Sharon (Vicky Krieps), who is convinced that she might be framed for the crime, hires Joe in hopes that he will uncover a different truth. This decision is initially met with confusion as Joe had previously only worked on trivial cases where the police were uninvolved, tactfully setting him up as the ultimate underdog.

“Diamond” opens on a stunning set filled with dark wooden antiques. Joe descends in a manual elevator wearing a 1920s-style suit and fedora before stepping into an old-fashioned coupe. The film’s gold-tinted cinematography and theatrical jazz score initially suggest a traditional period detective drama. Yet the illusion abruptly shatters when Joe exits his garage and is nearly struck by a Waymo, firmly placing the film in present-day Los Angeles.

Written and directed by Garcia, his character’s contrast is evident through both his performance and through the film’s technical elements, capturing both the stylized atmosphere of a 1920s noir and the hyper-modern culture surrounding Joe. The editing is particularly strong, filled with sharp zoom-ins, theatrical cuts, and energetic transitions.

As a character, Joe embodies every familiar trait of the Holmesian detective: He’s consumed by his work, evasive about his personal life, and motivated more by passion than money. He works directly against an ineffectual police force and claims to have only one friend, whom he explicitly calls Dr. Watson — an unsubtle nod to the original Sherlock Holmes stories. His character feels like a walking cliché, even attempting a James Bond moment by introducing himself as “Diamond, Joe Diamond.”

Joe’s exaggerated old-fashionedness makes him an enigma within his modern-day surroundings as he sports a suspiciously limited knowledge of modern trends. He shoots crime evidence with a black-and-white film camera and receives tips through handwritten letters. At one point, he even asks for the definition of a selfie.

Even though Joe borrows heavily from characters like Holmes and Bond, he lacks the charm and charisma that make those figures compelling. Garcia gives the strongest performance possible with the material, but the character nevertheless remains lifeless. Even during emotional moments that are meant to humanize Joe, the stale writing prevents any genuine feeling from emerging.

Much like the rest of the film, the dialogue is overloaded with platitudes. “Diamond” bleeds unoriginality. That is, until its final twist, which surprisingly recontextualizes the film’s banality. In a genre that has exhausted nearly every possible reveal, the film’s ability to genuinely surprise is undeniably impressive. Still, one clever ending hardly justifies the hour and a half preceding it, which never reaches the same level of imagination.

A murder mystery does not necessarily need profound thematic depth to succeed; its primary responsibility is often to entertain. However, “Diamond” moves at a sluggish pace and lacks the tension or excitement expected from a crime drama.

“Diamond” presents a genuinely compelling premise for both its detective and its central twist, but massively underperforms its own potential. Although the ending attempts to retroactively elevate what came before it, the slow pacing and uninspired writing leave “Diamond” a disappointingly mediocre crime drama.

—Staff writer Anat Goldstein can be reached at [email protected].