Demi Moore’s bizarre dance with Lenny Kravitz (PICS)

She’s just turned 50, but there’s no slowing down for Demi Moore. Partygoers were bemused by the Ghost star’s behaviour at the Chanel Beachside Barbecue in Miami on Wednesday.

Demi started dancing and gyrating in her chair while sitting next to rocker Lenny Kravitz, who looked embarrassed and tried to look away. The actress, who has a history of drug and alcohol problems, wasn’t seen drinking on the night, but onlookers say she was gulping down can after can of the energy drink Red Bull and seemed “manic”.

She seemed unaware at times that, while dancing in chic grey romper suit, she was exposing a lot of flesh.

“Demi was in a world of her own,” one onlooker told People magazine adding that the actress was definitely flirting with Lenny.

“Demi seemed to be dancing for the cameras,” said another onlooker. Although they weren’t pictured together, Demi’s new toyboy boyfriend Vito Schnabel (26) was at the event and she was spotted having a public kissing session later in the evening.

“They are definitely a couple. She is definitely more down to party than Vito,” a source told E! News.