Found this article from The Hollywood Reporter. The costume designer explains why she distressed the sweater. I think the way she talks about the clothes is a great glimpse into how important fashion can be in movies.
STYLE How the 'Knives Out' Costume Designer Chose Chris Evans' Perfect Sweater
9:00 AM PST 11/27/2019 by Lindsay Weinberg

Claire Folger
Chris Evans in 'Knives Out'
"He'd grown up privileged and used his money to buy fancy cars, to buy fancy clothes, but you could tell that he didn't necessarily appreciate those things," says Jenny Eagan of character Ransom. "The holes and the tatter gave him a touch of that disrespect."
Earlier this month, a Twitter conversation about the whodunnit film Knives Out spread online. It wasn't about the identity of the killer, but about a more harmless detail: a particularly cozy white knit sweater that Chris Evans wears onscreen.
"The only thing I will say about Knives Out is that, upon seeing Chris Evans in a sweater, the girl next to me gasped and said very softly and tenderly, 'Sweater,'" tweeted film reporter Anna Menta.
"I'm not sure if it's the sweater or who's wearing the sweater," jokes Knives Out costume designer Jenny Eagan to The Hollywood Reporter. "That might be part of it, too. He looks pretty great."
She and Evans chose the Aran cable-knit sweater during a fitting so rushed that she doesn't know the brand, just that it worked perfectly for his character Ransom, the spoiled grandson of acclaimed book author Harlan (Christopher Plummer), to convey his privilege and wealth while the audience tries to determine how Harlan died. Joining The Avengers star in the cast are Jamie Lee Curtis, Daniel Craig, Ana de Armas, Michael Shannon, Toni Collette, Lakeith Stanfield and Katherine Langford, who play the detectives and family members trying to solve the mystery in a Boston mansion.
Eagan dressed the characters in sweaters to set the tone: it's winter for this big family and the knits lend a sense of comfort that contrasts with the suspenseful storyline. "The sweaters gave it a cozy feeling. You couldn't detect anything," says the costume designer, who previously worked on Widows, Maniac and Catch-22.

Claire Folger/MRC
From left: Chris Evans and Ana de Armas on set with director Rian Johnson.
For Ransom specifically, director Rian Johnson wanted him to be "this eccentric spoiled boy," Eagan says. "He'd grown up privileged and used his money to buy fancy cars, to buy fancy clothes, but you could tell that he didn't necessarily appreciate those things." She liked the white hue not only because "it was a beautiful color with his eyes," but also because "wealthy people can always wear white — nothing ever gets dirty."
Eagan decided to add some holes and rips to Evans' sweaters (he wears a pale blue one in a later scene) to show Ransom's nonchalant attitude. "He just didn't care.... I imagine it laying on the chair in his bedroom and he just threw it on day after day," she says. "But giving it little nicks or little holes here and there, meaning he didn't take care of it...the holes and the tatter gave him a touch of that disrespect. It was a disrespect to the family, a disrespect to the name, a disrespect to his clothes."
During the process of creating the rips, Eagan would put on the sweater and imagine where she would pull at it if it was too tight. She envisioned the character negligently throwing it into the washing machine and dryer, shrinking it and then stretching it back out. She used tools like a Dremel or sandpaper to create the tears: "I don't get scared. I just go for it. Sometimes it feels natural, like the neck. You always know if it's made of knit, if you break a thread, it unravels."

Courtesy of Claire Folger
As spectacular as the sweater is, the other elements of Evans' wardrobe convey Ransom's overall arrogance: "There's a little bit of that attitude. He's better than everybody. He spends all of his money, but he doesn't have to fit a mold and be classic East Coast prep boy. It's a little bit of an edge." Take, for example, his classic dark Ray-Ban sunglasses worn in the Boston cold. "They just read pretentious to a certain degree, but not over-the-top. He's making a statement; he's always trying to make a statement. He draws attention to himself whether it be the car, the expensive coat, the expensive sunglasses," Eagan says.
And his fine wool cashmere scarf almost didn't make it into the film, as it was a last-minute addition.
"I remember the camera test, I said, 'Oh, what about a scarf?' And Rian was like, 'Oh, I don't think so.' I had put a wool one on him. It wasn't as colorful. It wasn't as decorated," she says, explaining that she found scarves in more autumnal colors that appeared more expensive. "I found this one and on the day, I said, 'What about a scarf?' We were on the day of shooting, so he goes, "Let's try it.' And it just came on and I think it's more of a question of 'Should we do it? Should we not do it? Is it too much?' And then he just wore it. It didn't wear him. It was melded in and it felt right in the moment." It's from Drake's Fall 2018 collection (shop this year's version for $225).
Looking back, she loves the choice: "The scarf punched it up and questioned, 'Who is this guy?' That eccentric 'I'm cooler than everybody else.'"
Eagan bought most of the costume options at places ranging from Barneys to boutiques in Los Angeles, Boston and New York, before working with the actors in the fitting room to select the final outfits. "That's where [what] we call the magic happens," Eagan says. "You're like, 'Wow this is perfect.' And that was kind of how Chris' whole fitting was. Everything went on and it's like, 'Well this is fast. OK great.' Because he just fits in clothes so well. Also it depends on the attitude they come in with. If they're really into it and they've thought about it a lot, it's very quick for them because they get it. They gravitate to it."
She says that was especially the case with Evans' tan cashmere coat from New York brand Theory. "He put it on and it was like, 'Wow,'" she says. "He was like 'This is comfortable.'... It just felt like a second skin to him." They had multiples of the coat (since two dogs jump on it and get it dirty onscreen), so Evans might have taken one home as a souvenir. "I do think he took one, if I had to guess," Eagan says. "I do remember him asking and I remember saying, 'You have to ask the powers that be.' But I do think he did take one of those."
Her work on Knives Out was completed quickly; she estimates she saw each castmember about a week before shooting, "so it was kind of fast and furious." The cast's interest in their characters enabled fast decision-making: "You get into a rhythm." Lee Curtis' fitting was like "boom, boom, boom" as well, Eagan says. "She was so excited. I remember her saying to me so much that she always wore black and that she never wore another color, but she definitely saw this character in lots of color and had a specific friend of hers.... She sent me pictures and she was like, 'This was just the character.' It was really specific and it really made it fun."

Courtesy of TIFF
Actors Shannon, de Armas and Jaeden Martell also sport sweaters onscreen, while Eagan and Johnson put Collette, who plays hippie character Joni, in natural and organic looks (often from Australian label Zimmermann) to convey her chill personality. All of Craig's costumes were custom-made.
The goal remained for Eagan to establish defined characters for each actor, but not make them stand out so much that it would give away who committed a crime. "Subconsciously I was probably thinking anytime I was trying to find something, 'How far can I push it without making them stand out? Without drawing too much attention to them?'" she says. "You had to keep them all warm and relatable to a certain extent. If not, it would just be icy cold and you wouldn't like them and you would immediately think that that was the one
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