The starlet was the centre of attention at a party thrown for The Hunger Games: Mockingjay, where she held court with Liam Hemsworth and Josh Hutcherson.
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Guests were taken by bus to a multi-million dollar mansion in Antibes overlooking the Mediterranean and thought to be owned by a Russian tycoon. The stone entryway was decorated with the franchise's signature Mockingjay sign, while staff wore goth attire.
Inside Jennifer was reported to be boogying away to Beyonce, Macklemore, Michael Jackson and Missy Elliot tune Work It.
She's sometimes known for being a klutz on the red carpet, but this time there were no trips or mishaps.
The vivacious blonde was elegance itself, smiling broadly and showing off her style in a series of chic outfits by Dior.
During the daytime photo call, she wore a midriff-revealing crop top and mini skirt.
For the evening party she had picked a blue mini dress with a black chiffon overlay teamed with eyecatching green earrings.
Earlier, the actress was at a do thrown by Vanity Fair where she was introduced to Justin Bieber.
The starlet asked photographers not to take pictures of her with Justin
On learning he was there Jennifer cried: "I want to meet Bieber" and organisers duly obliged. The two stars chatted for a few minutes away from photographers, so she said they could "meet as real people".
Her animated but demure appearance was a far cry from Oscars night when she indulged a little too much and ended up feeling ill.
Jennifer admitted on a chat show that her behaviour was so bad that Miley Cyrus told her off. Passing her on the stairs at Madonna's afterparty, the controversial pop princess warned her: "Get it together, girl".