Martin Scorsese executive-produces this gritty and hard-edged examination of loss centered on Martha (Kirby) and Sean (LaBeouf), a Boston couple reeling after a home birth ends in tragedy. Martha spirals into a messy, yearlong odyssey of grief, often pained discovery while also haunted by memories of what went wrong with the now publicly vilified midwife (Molly Parker), who she must face in court. Martha also has to answer to her domineering mother, played enormously by Burstyn in another career-topping turn of many. Sean, meanwhile, goes on his own journey inward and out of control as the pair try to pick up the pieces, even as they are rarely moving in the same direction.

During a recent virtual post-screening Q&A hosted by Netflix, Kirby shared how important the film’s ambitious 23-minute opening sequence was to her process of getting into character. It’s a harrowing opening that drops us squarely into their dynamic. Kirby confessed to feeling more scared by the possibility of doing “a birth that was edited and chopped up because, in a way, you’d have to get yourself into different stages of labor while cutting, going for a break, having lunch or whatever.” The continuous take, Kirby said, aided in their “intention to make it as authentic as possible.” Kirby said the team was determined to show “birth in all its glory, in its difficulty, and its pain, and its horror and its majesty.” She added, “I knew that I had to understand every minute of what labor was like,” eventually shadowing an obstetrician in a labor ward and even watching a full birth during the course of her preparation. The team shot the scene during the film’s first two days on set, with two takes a day. “We just had no idea if it was going to work, and we just came together as a little tribe and went for it,” Kirby said. “It was actually exhilarating. It was the best film experience of my life.” The actress also spoke to a number of women who lost babies similarly. “When I started the process of trying to get inside Martha and, really, the majority of the film is post-that trauma, I knew that I had experienced that particular kind of loss,” she said. “I managed to find some really brave women who really wanted to share their experiences… The more I spoke to them, the more I found how difficult society finds [it] to talk about it. A lot of the women I spoke to felt as if their bodies had failed in some way, or they had failed their child, so [they feel] the guilt that comes with that, as well as the self-blame.”

Kirby added that one of the women she spoke to described their grieving process as “the loneliest feeling in the whole world, and you feel so isolated,” a feeling that permeates much of Kirby’s work as Martha in the film. Netflix will release “Pieces of a Woman” in select theaters on Wednesday, December 30 before the streaming premiere on Thursday, January 7. Check out the film’s first trailer below.

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