Babies are unequivocally wonderful. Sweet, helpless creatures who can melt your heart with a smile. Endless promise, endless potential. Living evidence that humanity has a bright and glorious future.

And also selfish, squalling, screaming little poop machines, demanding, horrible, red-faced and completely, totally, exhausting. A week dealing with a colicky infant can feel like the worst medieval torture. Women know this: you would commit homicide for a nap; you would burn down a convent for a shower. And that’s not even counting how damaged and vulnerable and in pain and hormonal women feel anyway, after the agony and trauma of childbirth.

In Tully, Charlize Theron plays Marlo, a woman with two children, an eight-year old daughter, Sarah (Lia Frankland), and six-year-old son, Jonah (Asher Miles Falica), who has some sort of undiagnosed emotional disorder. Her husband Drew (Ron Livingston) is a moderately successful corporate middle-manager drone, and Marlo is on maternity leave from a job in HR. Comfortable middle-class family, not wealthy, in a pretty good, fairly mutually supportive marriage. Marlo, as the movie begins, is exceedingly pregnant, and twenty minutes into the movie, gives birth, to baby Mia. Marlo is at her wit’s end before Mia shows up, because Jonah, basically a sweet kid, is also impossible, given to uncontrollable tantrums when triggered by what essentially seem to be random events–parking in the ‘wrong’ parking lot, the sound of a toilet flushing, any foods that aren’t chicken nuggets.

And then Mia arrives. And Marlo is . . . empty.  Sleep deprived and exhausted, can barely function. But her much-wealthier brother, Craig (Mark Duplass) offers to pay for her to have a night nanny. I’d never heard of such a thing, but apparently it’s real. A night nanny comes to your house around 10:30, watches your baby overnight, brings her to Mom for breast feedings, but takes care of everything else. Enter Tully (Mackenzie Davis). And Tully is amazing. She’s kind, she’s cheerful, she’s wonderful with the baby, and she cleans the house all night so Marlo doesn’t have to deal with it. She bakes minion cupcakes for Jonah’s schoolmates. She counsels, supports, cajoles. She’s kind. She’s also kind of weird, with hippie-ish ideas about the relationship between Moms and babies, and with all sorts of random facts at her fingertips. (It’s also possible that she might be a mermaid). Marlo’s skeptical at first of Tully–does she even need this, what’s going on, can I actually trust this young woman? But in very short order, Marlo is transformed. She can actually sleep at night! She has energy again! She re-engages with her family, cooks nicer meals, apologizes to people who she had blown up at, even, weirdly, starts to regain something of a libido. Tully’s a lifesaver.

And now I have to stop telling you about the movie’s story, and just urge you to see it. If you’re a Mom, you absolutely must see this movie. And do whatever you need to to get your husband to see it with you. I say that as a guy–he needs to see this. Drew, her husband, is not a bad guy. He’s a good Dad, he loves his wife and family, he’s certainly not remotely unfaithful or whiny or more than normal amounts of selfish. Ron Livingstone’s a fine actor, and the character he plays is not in any sense a villain. But seeing childbirth and infant raising from a woman’s perspective, as we do in this movie, is salutary for us guys. He doesn’t do enough. He does help out. Not close to enough. We don’t, generally. Make him watch it with you. It’ll be good for him.

And don’t leave early. And you’ll probably want to. At first, I thought it was going to be about how super duper awesome it is to be able to afford a night nanny, and sort of wanted to hate it for class reasons–most women can’t afford one, many new Moms are alone, many can barely afford housing. But no, that’s not what this movie is about.  The relationship between Tully and Marlo takes some weird turns, and you may be tempted to give up on it. Again: don’t. I wondered if it was going to be one of those horror movies where the nanny seems super nice and awesome and ends up a demon from the pits of hell. That’s not this movie; not even a little bit. We get all sorts of false clues as to What Might Be Going On– I promise, you’re going to make guesses and those guesses will be wrong. The first half of the movie is very funny, and then it gets sadder and sadder, but please, please, stay with it. Trust me on this. It’s a wonderful movie, eventually. I mean, not conventionally ‘gosh, babies are wonderful after all!’ (The baby’s performance was pretty flat, I thought–essentially, just crying and pooping. The baby doesn’t really grow or develop as a character, I suppose because this movie mostly just covers the first month of its life. Babies don’t. Eventually they become teenagers. This is not a huge improvement).

But there are three other reasons to see it. First, is Diablo Cody’s screenplay. Sorry, that’s former stripper, now mother-of-two, Oscar winner Diablo Cody. She’s such a fine writer, truthful and funny and sad and real. Look at her screen credits: Juno, Ricky and the Flash, the upcoming Barbie movie. Her screenplay is a marvel, detailed and smart and so very intriguing. I won’t give away its secrets; just see the movie.

Second, Theron. Charlize Theron is a marvelous actress, and earlier that day I had seen some of her performance in Atomic Blonde, where she plays a kick-ass assassin femme fatale. Not this time. But she’s completely unafraid in this movie, to strip away all vestiges of movie star glamour, and just be a woman with a new baby who can barely cope. It’s just a terrific performance, funny when it needs to be, heart-breaking when that’s required.

Finally, it’s not a political movie, not even a little. But it also really is. It reminds us that most advanced nations offer–heck, require–paid maternity leave for families with new babies, for both Mom and Dad, for a year or longer. And that would make a difference. Having children is hard. Not just a little bit hard–exceptionally, heart-breakingly hard. Women’s bodies are amazing, and the babies are amazing, and families are wonderful, but there is nothing about childbirth and infancy that are easy. Only one major industrialized nation does not require employers to provide for maternity leave for both parents, and the reason is simple: Republicans. Pro-family Republicans. And no, nothing in the movie even suggests that political agenda. Except all of it does.

Anyway, see it. Watch it to the end. Make hubby see it too. It’s just really good. And then come home afterwards and give your kids a hug. Betcha anything they hug you back. Kids are great that way.