Overview: Following the death of his father, Jay Gardiner goes diving off the coast of California in search of his remains. He soon finds himself in a desperate fight for survival when he’s swallowed whole by a massive whale. Trapped inside its belly, he must figure out a way to escape as his oxygen supply starts to run out.

Verdict: Like the opposing ocean tides, forces that both contrast and complement each other, 20th Century Studios’ “Whalefall” is one compelling movie with two powerful narratives. The first is the one the marketing sells hardest: one man’s race against time in a desperate fight for survival. The second is the one that will probably affect audiences most: a father-son relationship where time has already run out.

Epic and emotional, “Whalefall” adapts the titular 2023 novel by Daniel Kraus, who co-wrote the screenplay with director Brian Duffield, known for writing “Underwater” and “Love and Monsters,” and directing Hulu’s “No One Will Save You.” The film follows Jay Gardiner, played by Austin Abrams (“Resident Evil”), as he returns home to California’s Central Coast following the death of his father, Mitt, a professional diver played by Josh Brolin (“The Dog Stars”). Through flashbacks, we discover that Mitt was an overbearing, rugged man who lived his life on and in the water. Revered by his community and peers, he was far less successful at connecting with his son, whose childhood under Mitt’s tough-love approach left him carrying years of resentment.

Terminally ill and choosing to die in the water, Mitt leaves behind a body that no one can recover, forcing the family to bury an empty casket. While Jay’s mother and sisters, played by Elisabeth Shue (“Leaving Las Vegas”), Jane Levy (“Evil Dead”), and Emily Rudd (“Fear Street”), process his passing in more traditional ways, the prodigal son dives alone in search of his father’s remains. Instead of finding what he’s looking for, however, Jay finds himself swallowed by a massive sperm whale. Trapped inside its belly with only an hour of oxygen remaining, he realizes that the hard-earned lessons his father imparted may hold the key to his escape. But first, he must confront the grief and anger he has spent years avoiding.

The marketing understandably leans into selling “Whalefall” as a survival nightmare, particularly with its October theatrical release in the weeks leading up to Halloween. And it certainly delivers on that promise. Yet there’s much more going on beneath the surface.

Jay’s initial underwater encounter is intense and thrilling, placing him in the middle of a ferocious confrontation between a giant squid and the whale before the creature swallows him whole. From there, the film shifts into a nightmare of panic and claustrophobia, complete with a second encounter with the squid, now a deadly roommate.

The clock starts ticking as Jay desperately attempts to map an escape route and overcome the life-threatening obstacles separating him from freedom. Anyone familiar with the digestive process can imagine some of the perils involved, while the vastness of the deep blue sea and the surface above become increasingly tantalizing possibilities. Viewers prone to claustrophobia may find much of “Whalefall” almost unbearable. Even without that particular fear, it’s difficult not to feel overwhelmed by the ferocity and intensity of Jay’s predicament.

Readers of the novel will know that an incident involving the whale and its passengers becomes a crucial turning point, transforming the increasingly frantic escape attempt into something else entirely. Here, “Whalefall” becomes an even more affecting story about human connection and the inescapability of grief. You can bury sorrow as deep as the ocean itself, but it never truly goes away. Anyone who has lost someone they love, a soulmate of sorts, will recognize the emotional terrain. What begins as a fight for survival gradually becomes a story about life, love, and release.

Grief can feel like drowning, like being trapped with no conceivable way out, or being swallowed whole by something too enormous to comprehend. Duffield gives those feelings a startlingly literal expression, crafting one of the most gripping cinematic metaphors in recent memory. And it’s here that the film delivers its deepest emotional punch.

From the action set pieces to the intimate human drama and the fever-dream-like third act, Abrams shows exactly why he’s become such a compelling screen presence, anchoring two of the year’s best cinematic experiences. His everyman appeal and emotional authenticity, coupled with an ability to hold the audience’s attention no matter how extreme the circumstances, make for a remarkably assured performance.

Few actors are as watchable right now. His scenes with Brolin are emotional powder kegs, and their natural chemistry lets them move effortlessly between a desperate search for trust, tenderness, and connection, and confrontations as ferocious as the battle between the squid and the whale. Their father-son relationship is its own turbulent ecosystem, as unpredictable and unforgiving as the ocean itself.

It’s also hard to miss Duffield and cinematographer Aaron Morton’s striking use of eyes and extreme close-ups, which, combined with Pietro Scalia’s editing, create a sense of mania and intimacy essential to the film’s effectiveness. At times, the visual language recalls Sam Raimi’s “Evil Dead” and even the heightened, nightmarish imagery of 1970s giallo cinema. Accompanied by Joseph Trapanese’s score, “Whalefall” becomes a disorienting maelstrom of shifting tones and sensations, swirling between terror and tenderness, and knowing precisely when to hit hard and when to pull back.