Charlize Theron has portrayed some formidable women. Her agent in “Atomic Blonde” challenged action movie gender roles, and her Imperator Furiosa was such a ferocious, feminist fighter that ‘men’s rights activists’ boycotted “Mad Max: Fury Road.” Her characters have faced dystopian overlords and alien abominations, but in “Tully”, Theron stares down the beast inside her belly—motherhood. 

Director Jason Reitman and screenwriter Diablo Cody, who previously made indie classic “Juno” and “Young Adult” together, reteam for this comedy-drama about postpartum depression. Marlo (Charlize Theron) is days away from having her third child and she is decidedly unprepared: her son’s behavioral issues are wearing her down, her husband (Ron Livingston) is blissfully unaware of how hard her job is, and her wealthy brother (Mark Duplass) is a pretentious picture of perfect parenting that’s putting the pressure on. 

Diablo Cody is a sharp screenwriter with the uncanny ability to hide fine points in the gaps of her story. Without expressly mentioning the issue, the first act of “Tully” asks whether or not it’s ethical to bring a child into a world of strain and financial drain. Marlo forgets about her new baby during conversations that are centered on it; there are inserts of well-adjusted children with wealthy and responsible parents; dialogue beats around a bush of parents being culpable for maladjusted kids. Cody’s question rings silent but shrill. 

Reitman has developed a visual language that pairs well with Cody’s storytelling. Though the film’s dialogue is naturalistic, its cinematography is not: it’s shot on a wider lens than films of this genre usually are, framing the ubiquity of motherhood in the wider context of situations affecting family life. This method allows Reitman and Cody to make subdued statements about how wealth inequality affects the American family. It gives “Tully” a rather brilliant start. 

But then Tully herself enters the scene. Marlo’s rich brother hires a night nanny once the new child is born, so Marlo can enjoy her family by day and actually rest by night. Mackenzie Davis, an actress with phenomenal range and depth, portrays nurse Tully—like pre-fame Brie Larson, she’s quietly been one of the best in the business, uplifting indies like this and “Always Shine” with dynamic elegance. At first, Tully represents everything that Marlo hasn’t been able to afford: physical prowess, education, freedom, and time. 

But as the movie approaches its third act, it becomes clear that Cody has stranger designs for the character. Watching “Tully” is like watching your child take the wrong direction in life: it barrels toward a ludicrous plot twist, leaving the realm of the understated and entering the overdramatic. It’s as unwelcome as it is predictable. The twist’s fallout is handled with grace, but it still hits you over the head with a painfully obvious metaphor. 

Charlize Theron is outstanding throughout. Weakness and power are the signs of any well-meaning mother, and Theron embodies both with an empathetic fullness. “Tully” makes motherhood seem terrifying—rightly so, I assume—and Theron’s performance demonstrates a close familiarity with the practice. 

Despite a wobbly finish, “Tully” is a thoughtful picture of a subject that there aren’t enough movies about. The first two thirds are essential, the performances even more so. 

★★★½ (3.5/5)