In terms of writers who pair with directors, few have the winning bond that scribe Diablo Cody has with auteur Jason Reitman. It lives in the unglamorous and sleepless postpartum haze of breast pumps and swaddles. Marlo, physically wrung out by childbirth - Theron gained a visible 50 pounds for the role - regards Tully's flat midriff and carefree attitude with a complicated mix of fondness, bitterness and suspicion.
It's well into "Tully" before we meet Marlo's savior: a 26-year-old night nurse (Mackenzie Davis), for whom Marlo's wealthier brother Craig (Mark Duplass) has paid.
There's an extraordinary sequence, just after the birth, a montage of night after night of sleep deprivation and of her entire existence, just about, given over to the insistent and never-ending demands of the screaming infant.
Marlo is less sure. Baby weight and cupcake panic are tag-teaming to smother any spark of life she once had. The film looks exactly like the inside of Marlo's mind, just as her exterior appearance reflects her internal struggle. Her tantrum-throwing son Jonah (Asher Miles Fallica) is labeled "quirky" by his school, but they mean worse and they want him transferred out. That it works as well as it does is thanks to a screenplay that largely drops Cody's signature sarcasm - so often used to mask painful underlying secrets - for a voice that is much more raw and direct. Laid-back yet eager to please as portrayed by Davis, Tully makes for a wondrously levelheaded and insightful foil to Theron's middle-aged mother, offering Marlo not just a sounding board for her anxieties about aging and inadequacy - as a parent, as a partner and as a person - but also a devil's advocate.
And, given the degree of difficulty involved, I'd say she's entitled. Cody's scripts are a bit too cute for me sometimes - and maybe it's because so much of the bittersweet comedy of parenthood resonated with me after raising twins - but I was thoroughly mesmerized by Tully, which had its WIsconsin premiere at this year's Wisconsin Film Festival. So it's not that big of a deal, ' she told Time Out London. The slightest turn of the dial and this would be a horror movie.
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Not since her 2003 well-deserved Oscar-winning performance as real life serial killer Aileen Wuornos in "Monster" has Theron - one of the most handsome women on the planet - thoroughly committed herself to playing a character who most people would not consider to be highly desirable. "It's like I can see in color again", says Marlo, who earlier in the film refers to her body as "a relief map for a war-torn country".
Tully is carefully embroidered with exquisite lines of pithy dialogue that demonstrate Cody's finely tuned ear for free-flowing conversation.
Jason Reitman is a filmmaker who has built his reputation around creating emotionally powerful dramedies involving unpredictable characters in such films as "Juno", "Up in the Air" and the vastly underrated and almost unseen "Men, Women & Children". "And to be honest, it probably would have been a better commercial impulse to do something like that because the smaller more intimate stories are being told on cable and streaming right now". He also has a knack for giving good actors room for stand-out performances.
Tully is nearly too good to be true, full of fun facts and homespun wisdom. Charlize would know - she has two kids of her own. It's surely one of the most authentic portrayals of young motherhood that we've had - and it's not like that's a much chronicled subject for Hollywood.
When the runner asks if she's OK, Marlo realises she's lactating - and the woman is severely grossed out. Then look at the birth statistics for nine months later.
"Tully", a Focus Features release, is rated R by the Motion Picture Association of America for "language and some sexuality/nudity".