TORONTO – “Motherhood is (expletive) brutal,” Amy Adams’ character says in her new movie “Nightbitch,” and she learns just how primal it can be when her life literally goes to the dogs.

Based on Rachel Yoder’s 2021 book, the darkly humorous drama (in theaters Dec. 6) features Adams as a woman who gave up her art gallery career to stay at home with her young son. She believes she’s turning into a dog when canine qualities start popping up on her body – including fur on her back, extra nipples and what seems to be a tail – and finds she's able to voice her internal anger and repression in a new way.

During a Q&A after the film’s world premiere Saturday night at Toronto International Film Festival, Adams said she signed on to star in and produce "Nightbitch" alongside writer/director Marielle Heller (“Can You Ever Forgive Me?”) after reading an early copy of the novel.

“I just so deeply connected to the narrative that Rachel created. It was so unique and so singular and just something I never read before,” she said.

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Yoder was also on hand and teared up a few times when discussing seeing her story on the big screen. “I thought I wrote a really weird book that no one would read, frankly,” she said. “So, yeah, it was really surprising then when this is what happened.”

Adams said she “honestly” doesn’t know why society can’t talk about the darker and more difficult aspects of motherhood. “One of the wonderful explorations of the film is this isolation that comes from that and the transformation of motherhood and parenthood. It's something that is a shared experience and yet it isn't shared.”

In general, “we're not very comfortable talking about female rage," Heller added. "It's not something that we tend to share with each other or talk about, and that we're sort of afraid of women at this phase of our lives. So it felt really good to kind of take this invisible experience that a lot of us have gone through and make it more visible.”

The director began working on adapting “Nightbitch” while “really postpartum” after having her second child, who was born in 2020. She was home while her husband, comedian/filmmaker Jorma Taccone, was off making a TV show, “so I was totally alone with two kids for the first time and just writing this during the naps. It was very cathartic. My husband was terrified when he read it.”

Scoot McNairy plays the spouse of Adams’ character in “Nightbitch,” a husband who doesn’t really understand what his wife's going through initially. “The one thing I did learn during this movie is don't mansplain motherhood,” McNairy quipped. “I hope that all of you guys learn all the things that I learned, which is shut up and listen.”

Adams worked with a bunch of canine co-stars, when her character begins to be approached by dogs and they communicate with her in animal fashion, dropping dead critters off at her door. Marielle reported that they used 12 real dogs on the set “with 12 trainers all hiding in bushes.”

In one scene, Adams’ increasingly canine mom walks down steps and is swarmed by the dogs in her front lawn. They got it down in rehearsals, but when the time came for Adams to film with them, she made a head tilt while in character that didn’t go over well. “The dogs freaked out and started lunging at her. It was like her behavior was too odd and it flipped them. It was wild,” Heller recalled.

“One dog was like, ‘That's not OK, that's not cool,’ ” Adams said. “No matter what I did, he didn't trust me after that.”