“The Theory of Everything” opens Wednesday at Point and Sundance Cinemas. PG-13, 2:03, three and a half stars out of four.

If Eddie Redmayne wins an Oscar for playing famous physicist Stephen Hawking in “The Theory of Everything,” Academy voters will probably be responding to the technical virtuosity of his performance. Portraying Hawking’s slow slide into near-immobility due to ALS, Redmayne looks and sounds uncannily like Hawking, with every twitch, every contorted movement just perfect.

But what makes “The Theory of Everything” a poignant film is that Redmayne (and director James Marsh) never loses sight of the mind — and the man — inside the deteriorating body. Redmayne conveys such humanity and brilliance within such a limited range of motion and expression that you never doubt for a second that there’s a living, thinking, feeling, loving person in there. It’s really an amazing performance.

Directed by Marsh (“Man on Wire,” “Wisconsin Death Trip”), “Theory” is based not on Hawking’s own “A Brief History of Time” (there’s a good Errol Morris documentary about that), but on the memoir written by his first wife, Jane Wilde (Felicity Jones). As a result, the film is much less about Hawking’s scientific inquiries into the origins of the universe, and much more about the origins of their love story.

The pair meet while students at Cambridge in the early ’60s, where aside from the occasional stumble and fumble, Hawking still has full use of his faculties. (Knowing what’s coming, it’s heartbreaking to see what a vibrant, even dashing young man he was.) Stephen and Jane are somewhat opposites — he’s a man of science, she’s a woman of faith — but their growing courtship is believable,

Hawking’s mischievous smile and wit proving irresistible for Jane. But then, of course, the diagnoses comes after Hawking takes a nasty fall in the school quad. A doctor tells him that he has about two years to live, as he gradually loses control of his body, though his mind will remain intact. “Your thoughts won’t change,” the doctor tells him. “It’s just that, eventually, no one will know what they are.”

It’s worse than a death sentence for Hawking, who tries to shut himself away, spending his remaining time working on his cosmology theories while he still can. But Jane determinedly draws him out, and the couple get married, start a family. Jones is a terrific actress (“Like Crazy,” “The Invisible Woman”) whose role is much less showy than Redmayne’s, but still deeply felt, as we see both the deep love Jane feels for Hawking and the emotional toll the marriage takes on her.

By focusing on the relationship, “The Theory of Everything” largely backgrounds Hawking’s scientific achievements, although it doesn’t dismiss them; this isn’t like “A Beautiful Mind,” which ended with the message that what’s really important in life is “a beautiful heart.” (Sorry, science.) We get some glimpses of Hawking’s genius, especially in his interactions with his mentor (a lovely and wry David Thewlis). The film could have used a little more science — I’m going to guess that Hawking, who fought Morris to keep his documentary focused on the science, wouldn’t be too crazy about it.

In addition to its terrific, authentic lead performances, this is a beautiful film to look at, with Marsh and cinematographer Benoit Delhomme coming up with one striking shot after another, often illustrating the way Hawking looks at the world. Playing off Hawking’s fascination with black holes, circles are a recurring motif — the swirl of cream in a coffee cup, the spinning of a bicycle wheel, an overhead shot of Hawking in his motorized wheelchair doing 360’s.

“The Theory of Everything” is a traditional, handsome, for-your-consideration biopic in many ways, as is to be expected. But it’s also deeper than that, and Marsh includes little grace notes and unexpected details that don’t conform to the established formula. There’s a scene late in the film when a nearly immobile Hawking fantasizes about getting out of his wheelchair. Does he fantasize about giving a powerful speech in his own voice, or sweeping his love into his arms? No, he simply fantasizes about picking up a pen that someone has dropped on the floor and giving it back to her.