Joaquin Phoenix. Courtesy of Merrick Morton.
Joaquin Phoenix. Courtesy of Merrick Morton.

In his quixotic films, the director Spike Jonze has dazzled audiences with portals into the minds of a movie star (Being John Malkovich), a neurotic writer (Adaptation), and an imaginative child (Where the Wild Things Are). But in real life, Jonze laments, "even with people we know well, we can never really be in their heads. We're stuck trying to understand." This sense of frustration is at the center of Jonze's new film, Her.

Set in a utopian Los Angeles of the near future, the film stars Joaquin Phoenix as Theodore, a man crippled by the demise of his marriage to Catherine (Rooney Mara). He begins a relationship with someone new—only she isn't the usual rebound: Samantha is the world's first artificially intelligent computer program, a fully sentient Siri of sorts (with Scarlett Johansson's purr). Theodore falls in love and, in teaching Samantha what it is to be human, learns something about the subject himself. Like all of Jonze's work, Her is not easily summed up or pinned down. "I'm not trying to explore any one idea about relationships and technology," the director says. "I'm trying to explore all the different ways of thinking about it." Straightforward answers, it seems, are just not his thing. "All of my movies have this aspect of constant evolution and exploration, which really means: We don't know what we're doing!"