Actress turned singer Juliette Lewis let her hair down on a crazy night out in Cannes last night - stunning her Hollywood contemporaries by groping new mum Cate Blanchett's breast.

The 34-year-old was the centre of attention at the Chopard and Alberta Ferretti party at Crystal Beach on the French Riviera as she danced alone in the centre of the dancefloor in her transparent dress.

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What a handful: Juliette Lewis gets to grip with Cate Blanchett's womanly post-baby figure at the Chopard/Alberta Ferretti party last night

Juliette left her band The Licks at home for the night as she showed off her DJing skills to the A-list crowd, which included Cate, Julianne Moore, Mischa Barton, Leonardi DiCaprio's girlfriend Bar Rafaeli and Devon Aoki.

Keen to show her support to Alberta Ferretti, who was hosting the party, Juliette looked stunning as she posed on the red carpet one of the Italian designer's the 1920s-style fringed mini-dress.

Juliette went beyond the call of duty as entertainment in the evening and after DJing, took to the dancefloor herself with a series of flamboyant moves.

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Dancing queen: Juliette Lewis shimmies on the dance floor... without her heels

After attending the opening ceremony of the Cannes Film Festival on Wednesday, a radiant Cate, who gave birth to her third child just four weeks ago, was ready to party with Juliette.

The two women were spotted locked deep in conversation at the Chopard/Alberta Ferretti, and at one point Juliette appeared to grope one of Cate's breasts.

Cate, who stars in the eagerly-anticipated Indiana Jones And Kingdom Of The Crystal Skull, and husband Andrew Upton welcomed baby Ignatius on April 13th, who joined Dashiell, six; and Roman, four.

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Glamour girl: A calm Juliette Lewis on the red carpet at the beginning of the night, in a transparent 1920-style fringed mini dress

Also at the bash was Israeli model Bar, who modelled a lilac silk chiffon jewel dress co-designed by Swiss jeweller Chopard and Ferretti.

The £555,000 gown, which is adorned with 2,904 carats worth of gems, will go up for auction at a American Foundation Against Aids charity diner on May 22nd.

Last night a DJ saved my life: Juliette spins the tunes

Girl talk: An animated Juliette humours Leonardo DiCaprio's model girlfriend Bar Rafaeli