Erin Carlson has something to get off her chest.

“When I started this book,” she tells The Lily over the phone. “I had not seen every single Meryl movie.” To be fair to the writer of “Queen Meryl,” a new book out Sept. 24 that looks at the actress’s impressive filmography, Streep has done over 60 films in her 43-year career, with two more (“The Laundromat” and “Little Women”) due out this year. It’s not easy keeping up with the 70-year-old actress.

“She’s a character actress,” Carlson says, “and sometimes we want to see her as a leading lady.”

However, Streep wants to be seen as a blank slate, which adds to her mystery. In Carlson’s interviews with Streep’s friends and co-workers, many questioned whether they even know the real Meryl Streep.

“She’s almost running from us,” says Carlson, who wasn’t able to speak with Streep for the book. “We’re trying to box her in and corner her, especially me as a biographer, but she’s not going to do that. She’s just going to keep us guessing, and it’s frustrating, but that’s also part of her magic. We don’t really know this woman.”

The closest most of us will get to actually understanding Streep is through her movies. Whether she’s playing the boss from hell Miranda Priestly or real-life activist Karen Silkwood, Streep is always working to “show the lives of women who are overlooked, undervalued, and whose interior lives aren’t given the same weight or specialness or attention as the lives of men,” Carlson says.

“She’s trying to give them dignity.”

Streep does this by fully inhabiting every character she plays through costumes, makeup and spot-on accent work. After “Sophie’s Choice,” for which Streep learned a Polish accent, Carlson says she became “the standard” to whom “other actresses compared themselves.” All of this is why it’s so difficult for Carlson to pick a favorite Streep role. When we spoke in early September, Carlson opted for “Julie & Julia.”

“I want to retire in a Nora Ephron movie,” she says. That response is fitting — Carlson previously wrote “I’ll Have What She’s Having,” which explored how Ephron saved the rom-com. “This second, that’s my favorite Meryl movie. Tomorrow it will be ‘Silkwood.’”

Without hesitation, Carlson can tell you which movie she wishes Streep had a role in: “Thelma & Louise.” During her research for the book, Carlson learned that Streep lobbied hard for her and bestie Goldie Hawn to star in the film, with one request: They change the now-iconic ending to something a bit more hopeful. That’s likely what lost her the role that eventually went to Susan Sarandon. “It was a punk rock ending,” Carlson says. “Meryl is not punk rock.”

Let’s be honest, that’s one of the few things the artist formerly known as Mary Louise Streep is not. After seeing all of Streep’s movies, Carlson wouldn’t dare say she’s an expert in all things Meryl, but it made her appreciate the iconic actress’s work so much more.

“Watching every single movie she’s done, I think what I discovered about Meryl was she has an inner child that she keeps aflame and she has never been jaded, not once,” Carlson says. “It’s how she sustained a career in an industry where women are just kind of tossed away at a certain age. So I’m just sitting here watching her, just still amazed by her.”

Below, Carlson shares seven films that show Streep’s range — and exhibit why she remains Hollywood royalty.

What it’s about: A 1960s stay-at-home mother (Streep) whose spouse and children are away on a trip meets a photographer (Clint Eastwood) with whom she has a brief affair.

Why it’s important: Carlson calls this “a heartbreaking and beautiful movie, kind of a European art film, and it was the symbiosis of two artists who understand the power of restraint,” she says. “Clint Eastwood, for all of his issues — the empty chair, oh my god — is an incredible artist who has this kind of judgment and economical approach to filmmaking that you just can’t train or fake. He’s a minimalist and that’s what makes his movies so emotional and powerful. And he let her shine. He kind of gave the movie to her and she was able to tell the story of a frustrated housewife, an Italian war bride who wanted something more out of her life. People are like, ‘Oh that’s a chick flick, it’s a weeper, it’s so melodramatic.’ Yeah, it’s a melodrama, but it also spoke to women who saw themselves in that character, who wanted something more out of their lives.”

A Cry in the Dark” (1988)

Meryl Streep and Sam Neill in “A Cry in the Dark.” (Entertainment Pictures/Alamy)
Meryl Streep and Sam Neill in “A Cry in the Dark.” (Entertainment Pictures/Alamy)

What it’s about: An infant disappears from an Australian campground. The child’s parents, Lindy and Michael Chamberlain (Streep and Sam Neill), fight to prove that they aren’t responsible. The film is based on a true story.

Why it’s important: “Meryl advocates and defends her characters,” Carlson says, even if they’re portrayed as villains, like Lindy Chamberlain was. “She defended the hell out of this character, who has been tainted by that trial and the death of her infant daughter. She’s infamous, but Meryl was able to humanize her.” The real-life “Lindy Chamberlain wasn’t a good actress, she wasn’t able to convince anybody that she didn’t kill her kid because she wasn’t willing to play by the rules of socially acceptable femininity. She just refused to do that,” Carlson says of Chamberlain, who was convicted of killing her daughter in 1982 then exonerated in 2012, 32 years after her child’s death. “I think Meryl was attracted to that role because she maybe saw pieces of herself in it. She wants to speak the truth of women like that. Those are the women who were killed in the Salem witch trials, they are Amanda Knox, they are Hillary Clinton. She was attracted to that and wanted to humanize these women.”

Silkwood” (1983)

What it’s about: Karen Silkwood (Streep) works at a nuclear facility and begins investigating and calling out safety violations that could endanger workers. The drama is inspired by a real-life whistleblower and labor union activist.

Why it’s important: Carlson calls Streep’s work in this movie “extraordinary.” Streep frustrated Nora Ephron, who wrote “Silkwood,” Carlson says, because Ephron “had this idea of what a Texas lab technician would look like and Meryl wanted to wear a miniskirt. Meryl saw the character of Karen Silkwood as a provocateur, which Nora came to see her as, too. She was a working-class woman, but you see her become radicalized once she joins the union and she looks around her and says, ‘Wait, I’ve been working in these conditions and I haven’t even noticed how bad it is.’ And then she gets exposed to radiation and the scene where she is scrubbed is heartbreaking and terrifying.”

The actual Karen Silkwood, Carlson adds, was “kind of like a Che Guevara-style face of the labor movement for feminists and nuclear activists, but Meryl made her human. She just wasn’t this union rabble-rouser, she was us, everyday Americans.” (To strike the right “Texas twang,” Streep “went to shopping malls and observed people and how they talk,” Carlson notes.)

Ricki and the Flash” (2015)

Meryl Streep in “Ricki and the Flash.” (Pictorial Press Ltd/Alamy)
Meryl Streep in “Ricki and the Flash.” (Pictorial Press Ltd/Alamy)

What it’s about: Ricki (Streep), a musician, was married with children, but she abandoned that life behind to quench her thirst for rock star fame. When she returns home, she must grapple with the family she left behind.

Why it’s important: “People don’t talk about Meryl’s musicality enough, and I think Meryl would want us to. Music is so important to her — she had this incredible coloratura soprano voice, which was discovered in seventh grade when she was singing ‘O Holy Night’ in French. Music has been part of Meryl’s art forever,” Carlson says, but in this film, “she has Elizabeth Holmes-ed her voice so that it is super low and husky. Just when you think you know this character, who’s singing Tom Petty covers and is a [George W.] Bush supporter, this woman reveals layers of herself that are deeper than you expect.” Having marathoned Streep’s movies, Carlson says that “‘Ricki’ was a refreshing burst of air because this character was completely different.”

The Devil Wears Prada” (2006)

Meryl Streep in “The Devil Wears Prada.” (Collection Christophel/Alamy)
Meryl Streep in “The Devil Wears Prada.” (Collection Christophel/Alamy)

What it’s about: A recent college graduate (Anne Hathaway) snags a job at an esteemed fashion magazine where she struggles to meet the demands of her dictatorial boss, Miranda Priestly (Streep).

Why it’s important: “Meryl has this fan base, this younger generation,” Carlson says, that “I don’t think had seen her before this. They worship her in that movie as a pseudo-Anna Wintour, which is so interesting to me. They didn’t worship Anne Hathaway — she hits too close to home.” According to Carlson, men approached Streep after she appeared in the movie, and said things like, “‘Oh, I really identified with Miranda and all that she has to go through.’ And she’s like, ‘Really?’ It frustrated her.”

Streep also made her mark on the screenplay, Carlson says. “In the original script, Miranda says, ‘Everyone wants to be me,’ but at the table read, Meryl changed that to, ‘Everyone wants to be us.’ Miranda is not a narcissist. She makes these power grabs but she does it for the good of the magazine, not herself. She’s there as a steward of the most important fashion bible in the world and she feels incredibly responsible for that. Meryl changed that line and it made all the difference.”

Plenty” (1985)

What it’s about: During World War II, a young English woman (Streep) fights for the French Resistance. After the war, she struggles to maintain a fulfilling life.

Why it’s important: “Plenty” is Carlson’s “favorite Meryl movie no one’s heard of. It’s so overwrought and unintentionally funny, also heartbreaking. There’s a sex scene with her and Sting that has to be seen to be believed.” To Carlson, “Plenty” is one of Streep’s “finest performances because it shows how frustrating it was for a woman” in the WWII era. “Her character was a debutante that became a spy in occupied France and her life was in danger every single day. She was thrilled and excited by it, and then finally she goes home, marries a diplomat, played by Charles Dance, and her life is reduced to drawing conversation from boring diplomats at dinner parties every night, having to play that role of the dutiful wife.”

Doubt” (2008)

Meryl Streep in “Doubt.” (Moviestore collection Ltd/Alamy)
Meryl Streep in “Doubt.” (Moviestore collection Ltd/Alamy)

What it’s about: When the first black student is accepted at a Catholic elementary school, the nun serving as the school principal (Streep) begins to suspect that a progressive priest (Philip Seymour Hoffman) who pays close attention to the boy may be sexually abusing him.

Why it’s important: “This was the only movie that I had seen in 60-plus of her movies where the male character matched her,” Carlson says. “Philip Seymour Hoffman is her equal in intensity and ferocity and commitment. Director and writer John Patrick Shanley wanted Tom Cruise in that role, but I’m so glad he cast Philip.” On the set, Carlson notes, Streep was “needling” Hoffman, “trying to get a rise out of him and walking around muttering under her breath, ‘I’m going to get you.’ It unsettled Philip — he started seeing her as an adversary, rather than his equal, so they were in the ring together and he wanted to break her down. He wanted to defeat her. He’s the only actor that I’ve seen be able to stand up to her and match her. But to me, Meryl won that round.”

We finally watched it: From ‘Schitt’s Creek’ to ‘Seinfeld,’ we’re catching up on the pop culture we missed

We assigned each other a show, movie or album. Try it with your friends.

11 movies for cooped-up kids that pass the Bechdel test

There are options other than ‘Frozen’