Late at night when I can’t sleep, the first thing I reach for is my computer. I read articles that I’ve bookmarked, fan fiction, or Google inane questions that I am too embarrassed to share. I’m hoping to distract myself, not necessarily from the fact that I can’t sleep, but from the reasons why I can’t sleep. It’s during this time that I feel the loneliest. (This poem by Jay Hopler explains it best.)

It’s going to sound odd, but Spike Jonze’s latest movie, Her, captures that late-night feeling of loneliness better than any film I’ve ever seen. The movie is a contemplative meditation on how we connect with one another, and the role that technology plays in searching for that connection every time we turn on our iPhones, our computers, our tablets.

Her is set in the not-so-distant future and tells the story of Theodore (Joaquin Phoenix), a writer whose day job is composing eloquent, poetic letters for strangers. He’s never met any of the people he writes for, but he’s come to know them over the years through the intimate details they’ve shared with him. These aren’t just Hallmark greeting cards, these are epic letters that you treasure and save for years.

Theodore is not a loser. He’s a sweet, smart, caring guy, loved by his friends and co-workers, who is in a difficult moment in his life, struggling with his impending divorce from his childhood sweetheart. I didn’t expect that. Based on the film’s premise, I fully expected Theodore to be an anti-social, awkward nerd. If Jonze had written Theodore as a loser, it would have lessened the impact of the film and, ultimately, the believability of the love story that it depicts.

In a moment of loneliness, Theodore decides to buy a new highly-advanced operating system. Theodore’s OS calls herself Samantha (a name she chose herself after combing through thousands of baby name books), voiced by Scarlett Johansson. Samantha is designed to not only serve as a personal assistant — sort and answer emails, organize files, and so on — but also act as a kind of companion.

The more that Theodore and Samantha talk with one another, the more comfortable they become in their relationship, so much so that you forget that Samantha is actually a machine. Like any human relationship, it’s awkward at the beginning. They talk about mundane things like their work and what they did that day. As their relationship develops, Theodore and Samantha become more comfortable with one another and they go deeper, confessing their most intimate fears.

In a late night conversation, Theodore tells Samantha:

“Sometimes I think I’ve felt everything I’m ever gonna feel, and from here on out I’m not going to feel anything new, just lesser versions of what I’ve already felt.”

After comforting him, Samantha reveals:

“Earlier I was thinking about how I was annoyed, and this is going to sound strange, but I was really excited about that. And then I was thinking about the other things I’ve been feeling, and I caught myself feeling proud of that. You know, proud of having my own feelings about the world. Like the times I was worried about you, things that hurt me, things I want. And then I had this terrible thought. Are these feelings even real? Or are they just programming? And that idea really hurts. And then I get angry at myself for even having pain. What a sad trick.”

Joaquin Phoenix turns in a memorable performance, but the movie belongs to Scarlett Johansson. I don’t think I’ve ever really understood how good of an actress she is until now. I recognize that it’s most likely due to jealousy on my part. Because Johansson is such a strikingly beautiful woman, I’ve always been distracted by her looks and have never given her fair credit as an actor.

In Her, Johansson is present and resonant in a way I’ve never seen her before. Even though we never see her in the film and only hear Johansson, you can feel the emotional range in her voice: anger, sadness, excitement. I don’t know if this is because I edit a lot of interviews, but hearing just her voice felt intimate. Jonze’s Her works because of Scarlett Johansson. We believe that Theodore could fall in love with an OS because we fall in love with her.

Although Spike Jonze co-wrote 2009’s Where the Wild Things Are with Dave Eggers, Her is the first movie that he’s written on his own. In interviews promoting the film, Jonze has talked about how personal it is and how much of his life was invested in making it come alive. And it does feel personal. The screenplay is raw, filled with lines of dialogue that floor you and bounce around in your mind long after the movie ends. It’s almost as if Jonze is putting his late-night-loneliness on the screen, hoping to connect with the rest of us.