Theodore Twombly (Joaquin Phoenix) is a sensitive and lonely man with a big heart who lives in an apartment in Los Angeles somewhere in the near future. He works at, where he is adept at expressing emotions in love notes written for and to strangers.

But as far as his own love life goes, he's been running on empty since his marriage to Catherine (Rooney Mara), a lawyer, ended. They'd been together since childhood, and he is still mourning the loss of this relationship. Among the things on his to-do list is to meet with her to sign the divorce papers. In the meantime, he is not adjusting well to single life. Theodore's chief pleasure seems to be playing a holographic video game that has a foul-mouthed virtual character who makes him laugh.

Theodore's best friend is Amy (Amy Adams) whose marriage is falling apart and who shares his love of video games. She wants him to leave behind "the sad, mopey you." His desperate need for connection with the opposite sex drives him to seek out some phone sex, but he connects with a woman who orders him to "choke me with a dead cat!" Later, he does go out on a blind date (Olivia Wilde) and things seem to be heading in the right direction until she criticizes his kissing style and then deals a death blow by mentioning that she doesn't want to waste any time with him if he can't make a "commitment."

No wonder Theodore makes the bold decision to ditch flesh-and-blood women for a different kind of relationship. He purchases a new operating system (OS1) that can run on his computer or his mobile device. This product's advertisements promise it's "not just an operating system — it's a consciousness."

Theodore installs the program, answers a few set-up questions, and then the OS tells him that she is Samantha. She begins as an efficient helpmate organizing his email, reminding him of important appointments, and perking him up in the morning or reviving him at midday with her energy. In these activities, she comes across as a mother figure who pays close attention to Theodore's moods and emotions.

Samantha soon assumes the role of his best friend. She is always there when he wants to talk, and Theodore feels he can share his most intimate feelings with her. Before long he is calling her his girlfriend (which, surprisingly, is accepted matter-of-factly by his friends) and is falling in love with her. Then it is time for the moment they have both been waiting for: sex together with his body and her disembodied voice. Later, Samantha is all lovey-dovey: "Can I watch you sleep again tonight?"

On one level, Her is a fresh and beguiling adult romantic drama. Writer and director Spike Jonze has already proven his ability to take us on cinematic journeys that are both weird and wild. He accomplished that with Being John Malkovich, Adaptation, and Where the Wild Things Are. Samantha is a portable gadget who becomes more important to Theodore's well-being than any of the people in his life. Scarlett Johansson provides the perfect voice for this artificially sentient companion. Samantha's greatest act of loving support of Theodore comes when she selects , edits, and finds a publisher for a collection of his love letters.

Jonze manages to convincingly convey these advantages of the interactions between Samantha and Theodore and also some of their drawbacks. He shows how this evolving operating system comes to dominate every aspect of Theodore's life, and we watch the familiar scene of a human being dropping whatever is happening in the real world to immerse himself in a relationship with an artificial companion. Yet this connection enriches them both. He says gratefully, "You know me so well!" And Samantha confesses: "You helped me discover my ability to want."

There will be those who point out that Samantha is nothing more than another male fantasy about a woman who serves all his needs and requires very little in return. But after the infatuation wears out its welcome, the relationship between Samantha and Theodore hits some rough patches. He is turned off when she suggests they have a sexual surrogate (Portia Doubleday) with a body stand-in for her as a lover. He begins to question some of her breathy speech affectations since she, after all, doesn't need air. But the biggest challenge to their relationship is her ability to evolve, to improvise, and to create (she composes musical numbers.) He simply can't keep up with her.

With astonishing performances by Joaquin Phoenix and Scarlett Johansson, Her is our favorite film of 2013. The always daring and creative writer and director Spike Jonz manages to mesmerize us with a story that explores the complicated interplay between a human being and a computer operating system while also revealing the universal challenges to intimate relationships of the heart. (We reflect more on this here.) Jonze leaves it to Amy to give us the line we've been pondering since seeing this film:

"We are only here briefly. And while we're here, I want to allow myself joy."

Screened at The 51st New York Film Festival, October 2013.