First came the TikTok lights, then the TikTok yoga pants and finally, this summer, the TikTok necklace: a three-strand Vivienne Westwood pearl choker first shown in 1990 that has popped up in certain stylish corners of the app.

The necklace, which imbues prim pearls with a bit of punk, is one of many vintage Westwood items that have found young fans online, thanks to a combination of factors: famous brand-boosters (Rihanna, Zendaya, Dua Lipa, Bella Hadid and Lisa Manobal of the K-pop group Blackpink, to name a few); nostalgia for clothing made from the ’90s and mid-2000s; and the resurgence of a stylish anime television series from that era called “Nana.”

Released in 2006 and based on a manga series by the Japanese author Ai Yazawa, the show follows two women in their early 20s, both named Nana, who meet on a train and become roommates. One of them is the front woman in a punk band and wears lots of Vivienne Westwood jewelry and clothing.

“I was into the Sex Pistols, and in high school a friend introduced me to ‘Nana,’ which combined my love for punk music and Vivienne Westwood,” said Skylar Rae Echard, a 20-year-old student in New York City who has posted about the brand and the show on TikTok. For her, Westwood — with its slinky corsets, low-waisted trousers and spiky statement jewelry — “has been the definition of edgy cool for a long time.”

Sydney Brams, a 23-year-old from West Palm Beach, Fla., said that one of her most popular TikTok videos features a Westwood corset top that she bought at a thrift store for $65; similar pieces can go for hundreds and even thousands of dollars on Depop, 1stdibs and eBay. Discovering a piece like that in a shop, Ms. Brams said, is “like finding a unicorn.”

Millie Adams, 23, who owns an online vintage shop called Studded Petals, saw a similar response when she posted a video in which she unboxed a 1991 Westwood bustle skirt. “I’ve been a fan since I was a teen and admire that her pieces were unique,” she said.

For some consumers, buying Ms. Westwood’s clothes and accessories secondhand is in line not only with a shift toward sustainable shopping but the designer’s own climate change activism. The designer is a spokeswoman for the environmentalist group Climate Revolution and has a history of protesting political issues like fracking and Brexit, both on and off the runway.

“In my small way, I’m doing my part for our environment, and I’m glad to support a brand that holds the same moral values I do,” said Emily Vu, a 24-year-old social media manager in Los Angeles, who has posted about her Westwood acquisitions on TikTok.

Some fans are more singularly focused. “I like her jewelry because of ‘Nana,’ I admit it,” said Caroline De Moura Gomes, 23, who is based in Lyon, France. In a TikTok video, she surveys her collection of the brand’s orb earrings and armor rings and corresponding scenes from the anime.

Tahsin Zahra Hussain, a 20-year-old fashion student in London, originally discovered Westwood’s work through Tumblr, but it wasn’t until she began watching “Nana” that she learned about individual pieces. Through the anime she came across the designer’s Rocking Horse shoes, which she later bought and revealed in an unboxing video on TikTok.

It’s not unusual for products to go viral on TikTok and set off consumer frenzies. Fashion is no exception: Pleated tennis skirts and Prada’s chunky loafers are among the items that have sold well following enthusiastic reviews on the platform.

Fervor for Westwood has caused searches to rise on resale sites. “We saw an 80 percent spike in queries for Vivienne Westwood between December 2020 and January 2021, and it has remained stable,” said Michael Ford, a senior trends researcher at Depop, citing celebrities as a driving force.

Poshmark has seen similar interest. “Searches increased 131 percent from last year with Vivienne Westwood bags up 310 percent. The term ‘pearl necklace’ is up 38 percent, and we hypothesize that TikTok has an impact for the drive in demand,” said Steven Tristan Young, the company’s chief marketing officer.

“We’re obviously delighted that another generation is discovering Vivienne’s work,” said Christopher Di Pietro, Vivienne Westwood’s global brand director. “Young people have always found her passion and singular vision very attractive.” (The designer herself was not available to comment.)

Pandemic idleness has played a role, too, in the rise of TikTok-inspired shopping. “I’ve been exposed, due to the algorithm, to more things I’d buy,” Ms. Hussain said. “We’ve been sitting at home with nothing to spend money on except material goods, so if I see a piece that I find pretty, I’ll get it.”