“Fathom,” a curiosity-driven documentary by Drew Xanthopoulos, is fascinated by two types of waves. It opens with a small boat on an overwhelming vista of water, then cuts to a computer analysis of the visual patterns in whale songs two scientists have left their lives behind to record.
On the fringes of Alaska, Dr. Michelle Fournet wants to communicate with humpback whales — to not just listen, but converse — using a playback machine of growls, swops and whups that’s taken her a decade to develop. (An early attempt sounded like the cetacean Minnie Riperton.) Nine-thousand miles south, Dr. Ellen Garland tracks the spread of one whale tune from Australia to French Polynesia, testing her hypothesis that whales have a shared culture similar to how humans fall under the thrall of an earwormy pop hit.
As the title implies, Xanthopoulos is intrigued by the lengths — or, in this case, depths — a person will go to understand another species. At times, the doc feels like science-fiction without the fiction. Swap whales for aliens and these two doctors aglow with the thrill of discovery could double for Jodie Foster in “Contact” or Amy Adams in “Arrival.”
Since the film is more focused on the quest itself than its conclusions, the second half pivots to apply the doctors’ theories of connection to the assistants who’ve agreed to follow them off the grid. In a nod to her own research, Dr. Garland teaches a Ph.D. student a wire-winding technique passed down through four generations of biologists, while Dr. Fournet wrestles with feeling more adrift in a city than she does at sea.
“I have to remove myself from society and live in a world that is dominated by animals,” Dr. Fournet says. “And it doesn’t feel like a sacrifice. It feels like a release.” Sure, mankind has also evolved to be a social beast — but whales have more than a 40-million-year head start.
Not rated. Running time: 1 hour 26 minutes. In theaters and on Apple TV+.