Lily James flashes a glimpse of her side boob in

Lily James flashes a glimpse of her side boob in a dramatic white ruffled dress as she joins co-star Joe Keery at the premiere of Finally Dawn in Rome

Lily James was the epitome of elegance as she stepped out with co-star Joe Keery at the premiere of her new film “Finalmente l'Alba” in Rome, Italy on Monday.

The 34-year-old British actress stunned in a dramatic white ruffled halter dress that revealed a glimpse of her ample side boob.

Lily's beautiful dress with feather embellishments and a lush princess skirt ensured that all eyes were on her as she made her stylish appearance.

Meanwhile, Stranger Things star Joe, 34, cut a dapper figure in a bright red double-breasted suit, which he paired with a light blue shirt.

The Italian historical drama tells the story of Lily's aspiring actress in 1950s Rome as she is about to become engaged to a man.

Lily James, 34, was the epitome of elegance. Co-star Joe Keery, 31, at the premiere of her new film

Lily James, 34, was the epitome of elegance as she appeared alongside co-star Joe Keery, 31, at the premiere of her new film “Finalmente l'Alba” in Rome, Italy on Monday

The British actress stunned in a dramatic white ruffled halter dress that revealed a glimpse of her ample side boob

The British actress stunned in a dramatic white ruffled halter dress that revealed a glimpse of her ample side boob

She goes to Cinecittà to audition as an extra and is thrown into this seemingly endless night of discovering herself. Joe plays love interest Sean Lockwood.

According to Collider.com. The film's origins lie in the glamorous and ever-changing scene of old Hollywood after World War II.

This is a time that saw the making of classic films such as 1953's Roman Holiday starring Audrey Hepburn, as well as many “sword and sandals” films such as Elizabeth Taylor's high budget Cleopatra.

Written and directed by Saverio Costanzo, the cast of the film also includes Oscar nominee Willem Dafoe and The Idol's Rachel Sennott.

The director revealed that Antonaci's character is actually inspired by a real young woman named Wilma Montesi.

Earlier in the day, Joe and Lily posed for a photocall – 24 hours after they dined at luxury Italian restaurant Dal Bolognese.

The beauty cut a stylish figure as she slipped into a tailored black suit jacket, tucked into high-waisted trousers.

She paired her look with a pair of polished patent pumps and opted for minimalist accessories like simple silver earrings.

Lily's beautiful dress was decorated with feather embellishments and a lush princess skirt

Lily's beautiful dress was decorated with feather embellishments and a lush princess skirt

Lily's look ensured that all eyes were on her as she made her stylish appearance

Lily's look ensured that all eyes were on her as she made her stylish appearance

Lily accentuated her petite features with makeup and wore her brunette locks loose

Lily accentuated her petite features with makeup and wore her brunette locks loose

She turned heads on the red carpet before the screening

She turned heads on the red carpet before the screening

She made sure to showcase the dress's backless design

She made sure to showcase the dress's backless design

Lily posed next to the film's director, Saverio Costanzo

Lily posed next to the film's director, Saverio Costanzo

The Italian historical drama tells the story of Lily's aspiring actress in 1950s Rome as she is about to become engaged to a man

The Italian historical drama tells the story of Lily's aspiring actress in 1950s Rome as she is about to become engaged to a man

Meanwhile, Stranger Things star Joe cut a dapper figure in a bright red double-breasted suit, which he teamed with a light blue shirt

Meanwhile, Stranger Things star Joe cut a dapper figure in a bright red double-breasted suit, which he paired with a light blue shirt

LR) Michele Bravi, Sofia Panizzi, Rebecca Antonaci, director Saverio Costanzo, Lily James, Alba Rohrwacher and Joe Keery

LR) Michele Bravi, Sofia Panizzi, Rebecca Antonaci, director Saverio Costanzo, Lily James, Alba Rohrwacher and Joe Keery

Meanwhile, Joe looked incredibly dapper as he arrived for the shoot in a sharp navy suit.

The actor smiled as he posed in front of a post in his trendy ensemble – underneath he wore a colorful sweatshirt.

Lily is currently in an on-off relationship with musician Michael Shuman, while Joe is romancing Chase Sui.

In early November 2023, The Chron revealed that Lily had apparently rekindled her romance with her rock star boyfriend Michael.

She even raised the question of whether they were engaged because she was wearing a gold ring on her wedding finger.

Lily and Michael split in February 2023 after rumors they had grown apart, but were then spotted together at Glastonbury – despite their rumored split.