Photos |  Focus Features/A24

Charlize Theron plays a depressed, 30-something mom-of-three who hires a night nanny to help with the newborn in “Tully.” In “Eighth Grade,” an introverted teenage girl tries to survive the last week of her disastrous eighth-grade year before leaving to start high school.

The team behind the 2007 instant classic “Juno,” screenwriter Diablo Cody and director Jason Reitman, have created an indelible vehicle for star Charlize Theron with “Tully,” a dramedy that manages to temper its painfully realistic depiction of family life with flights of fancy.

Theron stars as Marlo, an intelligent, sardonic, extremely pregnant mother of two, suffering, it is suggested by her husband and her brother, from depression.   

Her wealthy brother (Mark Duplass) is also a parent of three kids, but he and his wife throw around money freely and ludicrously in their child rearing, so Marlo takes his offer to pay for a “night nanny” for his sister with derision. She thinks it’s wrong to let someone else bond with her newborn. After the baby is born, however, the pressing needs of the infant and Marlo’s other kids, particularly her overly sensitive son, who is on the brink of expulsion from kindergarten for what appear to be special needs, lead her to call the night nanny.

Enter Tully, a slim, young, hip free spirit whose almost preternatural comprehension of Marlo leads to a growing friendship between the women. They seem to be kindred spirits, and Tully comes to anticipate Marlo’s most complex problems.

As Marlo’s fatigue and depression seem to improve, she thrives along with her family, but her friendship with Tully threatens to supersede its boundaries. The chemistry and give-and-take between the two actresses is thrilling, and their intimacy is something unusual to see depicted on screen. Actress Mackenzie Davis (“Halt and Catch Fire”) is magnificent, holding her own with an indomitable Theron scene for scene.

It’s interesting to think that “Juno,” from a decade earlier in the lives of these relatively young filmmakers, was about teen pregnancy, while “Tully” checks in deeper into adulthood with a mother of three. Writer Cody had recently given birth to her third child when she wrote this film, and it certainly shows. I felt like I was looking into my own haggard face in the mirror a couple of times during Theron’s vanity-free performance, and an extended sequence of nighttime feedings and diaper changes is chillingly accurate. But the multiple times when friendly-but-clueless husband Ron Livingston describes his wife as “leaving” their kids “home alone,” only to have someone point out to him that he himself was there, are perhaps the most devastatingly on-the-nose moments. 

This film is funny but dark, complex and full of real peril. It’s not perfect. It is sometimes facile, and, strangely enough, some of the dialogue is lacking, which is odd because that is usually Cody’s greatest strength. On the other hand, the heart of this film beats more strongly than in any of her previous work, and the relationship between Tully and Marlo is vivid, profound and ultimately very moving.

Charlize Theron gives a performance that is at times bravely unlikeable and ugly, although this character does not compare to her reprehensible character in her earlier collaboration with Diablo Cody, “Young Adult,” which was sometimes hard to watch. Marlo is dangerously unhappy, but in an all too relatable way, and I presume Cody and Jason Reitman have brought their own maturity to a film that is about just that.

A twist at the end makes “Tully” even more special, a bitter, bracing valentine not just to motherhood, but to womanhood, and an exploration of the fact that those are not always the same things.

“Tully” is currently available to rent.