Megan Fox is a lady in red.

The Transformers star recently debuted a drastic style change, unveiling a vibrant red hair color and a textured bob on Sept. 5. And while the Jennifer's Body star has sported auburn tresses in the past, she took it to the next level with an extremely bright and bold shade of crimson.

As for what inspired Megan's new look? Her go-to hairstylist Dimitris Giannetos offered insight into her French bob and red velvet hue.

"We wanted something major that was jaw dropping for Megan," he exclusively told E! News. "Just like her fiery personality, this look is so bold."

And like the trendsetter she is, the 37-year-old wanted to switch up her style ahead of the autumn season.

"Megan was ready for a bold change," Dimitris added, "and now seemed like the perfect time, especially since red shades are on trend for the fall."

In terms of the products the hair colorist used to create Megan's red-hot look, he applied Lime Crime's Unicorn Hair Full Coverage Dye, which he said "made this transformation so easy and attainable."

"I simply mixed the bright red shades Valentine and Flaming Red and applied it to the hair in sections," he detailed. "It also includes conditioning ingredients, which is why I love using it, the color lasts and moisturizes your hair beautifully."

It's safe to say Megan is a fan of her transformation, as she was spotted out and about in New York City on Sept. 5.

While enjoying an afternoon outing with fiancé Machine Gun Kelly, the actress looked chic in a gray oversized blazer dress that she paired with beige thigh-high boots that featured a snake-skin-style print and was laced up on the sides. She also accessorized with layers of chunky silver necklaces and matching earrings. 

Because of Megan's neutral-colored attire, her red-hot 'do was definitely the mane attraction.

Moreover, the rapper also made a splash with his wardrobe, wearing a bright blue puffer jacket, striped shirt and coordinating pants.

Of course, Megan isn't the only celebrity to get into the fall season before it officially kicks off on Sept. 23. Keep scrolling to see which other stars have switched up their hairstyles ahead of autumn.

The actress recently debuted a bright red hair color and equally bold blunt bob haircut.

The Scream actress debuted a bubblegum pink style in August 2023.

The son of David Beckham and Victoria Beckham got his head shaved by Selena Gomez's little sister, Gracie Teefey, in August 2023.

The Can't Hardly Wait actress showed off her drastic hair change, debuting dark red hair and a blunt bob haircut.

The Second Act star unveiled bright blonde highlights in a new selfie.

The Kardashians star showed off her new bob hairstyle in a recent SKIMS video campaign.

The Hustlers star debuted a voluminous long bob and curtain bangs on Aug. 12.

Rachel Green, is that you? The Euphoria star appeared to take inspiration from Jennifer Aniston's Friends character with this layered look.

The Vanderpump Rules star debuted a platinum blond dye job in August 2023.

The '90s heartthrob debuted a newly shaved head, sharing on Instagram that "it's for work."

The "Say So" singer showed off her dramatic hair transformation on Instagram, debuting bright purple hair and a spooky spider design on the back of her head.

The Kick-Ass actress debuted a fresh bob haircut, which she hasn't rocked in quite some time.

The American Idol judge revived her signature style of 2008 and revealed baby bangs in a June 20 Instagram.

In July 2023, the SKIMS founder debuted a short bob, bringing to mind what has become her sister Kourtney Kardashian's signature style in recent years.

The Vampire Diaries actress debuted fringe bangs for the Los Angeles premiere of her new film Out-Laws in June.

The "Vogue" singer debuted an edgy shag haircut on June 11.

The Dance Moms alum proved you can be blonde and brunette at the same time with her recent hair change.

The High School Musical alum has entered her French girl era, after showing off her new curtain bangs.

The New Girl alum ditched her trademark brown hair and blunt bangs for a sky-high blonde 'do for her upcoming appearance on the '80s-based Apple TV+ series Physical.

The "Over It" artist headed into summer with a shorter cut and new hair color, debuting her blonde bob to Instagram in May 2023.

The X-Men star kissed her shoulder-length hair goodbye and debuted a pixie cut on May 26.

While attending the Louis Vuitton cruise show in Italy on May 24, Emma debuted curtain bangs—a style she often rocked in the mid-2010s.

The Sweet Home Alabama actress debuted wispy fringe bangs in a stunning selfie. 

The Poosh founder went back to her brunette roots, debuting a new look. As she put it on Instagram, she's a "brunette4lyfe."

Amid her ongoing transformation journey, the Rob & Chyna alum debuted a short pixie cut with shaved sides.

On May 15, the pop star opted for a bold hair color, rocking jet-black hair.

The Star Wars actress debuted her newly shaved head on May 10, writing on Instagram, "Happy without hair!"

On April 24, the Tangled actress debuted a fresh cut and fringe bangs.

The "Flowers" singer unveiled a drastic hair change, going back to her brunette roots, at The Daily Front Row's Seventh Annual Fashion Los Angeles Awards.

The TikTok star debuted a drastic hair change at Coachella 2023, unveiling a blonde bob look.

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