A 90s movie siren who starred in a hit romcom opposite the late Paul Walker was unrecognizable while running errands in Los Angeles.

This actress portrayed a bookish high school student who becomes the subject of a cruel bet in the hit 1999 film She's All That, which starred Freddie Prinze Jr. and Walker.

She also played a singer who is thrust into fame after unwittingly getting involved in a sinister plot to brainwash the youth of America in the 2001 musical comedy Josie and the Pussycats.

Another notable role was in the 1995 coming of age film The Baby-Sitters Club.

On Wednesday, the star channeled her She's All That role with smart black sunglasses as she did a spot of shopping at Costco and Home Goods in Burbank.

Can you guess who this star is?

It's Rachael Leigh Cook! 

The star cut an effortlessly chic figure in an all-white look consisting of a knitted tank top, jeans, and sneakers.

She even rocked a flawless white manicure.

The star carried her essentials inside a woven black bag as she trotted through the parking lot with her car keys in hand.

With her eyewear on, Rachael looked straight out of her hit film She's All That, in which her character Laney Bosworth sported smart glasses.

The movie was an instant hit in 1999.

It is about a high school hotshot Zach Siler (Prinze Jr.) who is dumped by his cheerleader girlfriend, Taylor (Jodi Lyn O'Keefe).

Desperate to revive his fading reputation, Siler agrees to a seemingly impossible challenge. He has six weeks to gain the trust of nerdy outcast Laney Boggs (Cook) -- and help her to become the school's next prom queen.

Rachael was just 18 when she shot the film and considered it a 'great proxy experience' to student life due to her limited experience in 'real' high school. 

'I remember thinking it was a great proxy experience having not gone to "real" high school for very long,' she told E! News in 2021. 'But the people in that movie, like Matt, Tamara Mello, who played one of my tormentors, and Freddie, I'm going to sound like a complete egghead, but I think of them as people I went to school with.

'I need them to be that for me and they don't have to agree. It's my reality. It was right around the time it would've been my real senior prom. And yeah, a fake prom would totally do!'

Rachael appears in one of the most iconic scenes in the film which sees her unveiling her makeover as she ascends down a staircase in a red dress.  

But the star didn't stress over the weight of the scene prior to filming.  

'I didn't give it a ton of thought frankly. Whenever things don't have a big page count, as a young actor, you don't give them a lot of bandwidth in terms of headspace or investment.

'I just thought, "OK, I just have to put this on and come down the stairs, do a little bit of dialogue and bond, not a problem. Let's do this." It just seemed like a fun scene. I had a lot more—not stress, but I probably put a lot more thought into the scene where I have to run away from a party and fall into gravel. It just had a little bit more punch.'

She also praised her co-star Freddie.

The duo lost touch after filming She's All That but reconnected after Walker died in a car crash in 2013.

'He's just such a wonderful human,' she said of Freddie. 'I just love that guy. But I probably didn't talk to him again [after She's All That] until a couple of years after Paul [Walker, who co-starred] died and realized you really have to reach out and take some initiative.

'So we got coffee and I remember saying to him, "I know we never really hung out very much after the shoot, but you have no idea what a big part of my life this ended up being." And he said something very Freddie-like, "Me too, dude. It's crazy." But I'm so lucky that it's someone as charming and as lovely as Freddie to share that with. '