She showcased her toned legs with a thigh-high split as tiny spaghetti straps helped hold the dress together.

The platform enthusiast stood tall in sky-high heels from London-based party shoe specialist D’Accori

The star screamed ‘Old Hollywood’ as she styled her platinum blonde hair with a classic side-swept wave and dramatic smoky make up.

Lady Gaga set pulses racing in a plunging peek-a-boo outfit with revealing thigh split (Image: GC Images)

The award-winning singer and actress portrays Italian socialite and convicted felon Patrizia Reggiani, who was convicted of hiring a hitman to kill her ex-husband Maurizio Gucci in Ridley Scott’s new film.

The poker face songstress later wowed in a second ensemble featuring a tan and camel leather Gucci monogrammed cape, teamed with a matching dress.

The accessories added to her over the top glamorous appeal as she carried a metallic Gucci Zumi bag and modelled statement Victoria Beckham aviators.CrossoutCrossout: New Apocalyptic MMOby TaboolaThe 35-year-old fashionista flaunted her assets with a plunging neckline (Image: GC Images)

She was joined by co-stars Jared Leto, 49, who looked dapper in a black suit and stunner Salma Hayek, 55.

She also stars alongside Al Pacino and Jeremy Irons in the flick.

The Academy Award winner spoke to Vogue about her upcoming role in the upcoming biopic.

She explained: “It is three years since I started working on it and I will be fully honest and transparent: I lived as her (Reggiani) for a year and a half.

The songstress later wowed in a second ensemble featuring a leather Gucci monogrammed cape, teamed with a matching dress (Image: GC Images)

“And I spoke with an accent for nine months of that. Off camera, I never broke. I stayed with her.”

She also revealed that she went so deep into the part she began to lose touch with reality.

Gaga admitted: “I had some psychological difficulty at one point towards the end of filming.

“I was either in my hotel room, living and speaking as Reggiani, or I was on set, living and speaking as her.

“I remember I went out into Italy one day with a hat on to take a walk. I hadn’t taken a walk in about two months and I panicked. I thought I was on a movie set.”

House Of Gucci has won rave early reviews from critics following its world premiere in London on Tuesday evening.