A creepy Christmas cartoon character comes to life

“Oh my God! You’re the girl from ‘The Polar Express,'” a tourist shouted at Nia Wilkerson.

Dressed in a pink nightgown, Ms. Wilkerson danced in front of the Christmas tree at Rockefeller Center in Midtown Manhattan for a TikTok video.

Over the next two hours on Monday afternoon, dozens more people stopped and stared. Many of them filmed her from a distance or asked to take selfies with her.

‘Wait, is that you? Real the girl from the movie?” asked a passerby.

The answer to that question is no. Ms. Wilkerson, a senior at St. John’s University in Queens, was 3 years old in 2004 when “The Polar Express” was released.

The film, a box office success directed by Robert Zemeckis and based on a children’s book by Chris Van Allsburg, has long been known criticism due to its brand of motion-capture animation, which gives the characters a creepy, zombie look.

Ms. Wilkerson, 22, said people have told her since she was in elementary school in Woodbridge, Va., that she looks like Hero Girl, a character in the movie also known as Holly. Later, a high school crush pointed out the similarity.

“That was heartbreaking,” she joked.

Since then, Ms. Wilkerson, who stands five feet tall, has embraced her digital doppelgänger. This is her fourth holiday season of making TikTok videos in the guise of Hero Girl. Her popularity grew every year. She almost has one now 250,000 followers.

Ms Wilkerson said she came up with the idea after seeing another woman on TikTok cosplaying as the character. “But she didn’t really look like her,” she said.

In “The Polar Express,” Holly wears pigtails and a patterned pink nightgown. Ms. Wilkerson opts for a variation on the look for her TikToks.

“It’s a seasonal gig,” she said, adding that she was recently swarmed by people in Elmo costumes while shooting a video in Times Square.

She was joined Monday by several classmates from St. John’s, who acted as her unpaid film crew. “My friendship is my payment,” Ms. Wilkerson joked, adding that she purchased the group food from the campus dining hall during the weeks of filming.

She used to suffer from social anxiety, she said, but her TikTok alter ego helped her overcome it. “No one in New York cares,” she said. “I would never do this anywhere else.”

Ms. Wilkerson, who studies television and film at St. John’s, has found ways to capitalize on her 15 minutes of seasonal fame. She participates in TikTok’s creator fund, a program the company uses to pay certain people who create videos for the platform, she said. Musicians have contacted her about making videos, she added. Her rate is about $250 per video, she said. Outside the holidays she makes videos about other topics, but her perspective on things is quickly diminishing.

While most of the feedback was positive, Ms. Wilkerson said she stopped reading comments on her videos after seeing too many racist comments. Still, there are positives to her social media fame, such as a recent collaboration with @jerseyyjoe, a popular TikTok creator known for his dance moves and who sometimes makes videos dressed as Hero Boy from “The Polar Express.”

After an afternoon of filming, Ms. Wilkerson and her friends discussed their upcoming final exams while waiting for an F train on a subway station platform. Ms. Wilkerson mentioned an earlier subway video in which she accidentally kicked a passenger.

After boarding a train car during rush hour, they squeezed into formation to film another TikTok. One of Ms. Wilkerson’s friends, Amanda Gopie, 20, pointed to a sign that read: “Don’t be someone’s subway story.” Courtesy counts.”

“You are,” said Mrs. Gopie, to laughter from the others in the group.

As the F train headed toward Queens, Ms. Wilkerson and her friends recorded themselves singing “When Christmas Comes to Town,” a song from “The Polar Express.”

“The best time of the year, when everyone comes home,” Mrs. Wilkerson began.

As her friends joined in, forming a shaky choir, a few riders raised their heads in recognition. One of them told the singers to work on their pitch. The group decided they would try a different take.