Billy Crystal and George Clooney share kiss at 2012 Oscars

A fairly safe 2012 Oscars ceremony was livened up by a surprising smooch between host Billy Crystal and star George Clooney at the start of the ceremony.

Watch it below.

Crystal, back hosting for a ninth time after Eddie Murphy pulled out, leaned into Clooney and kissed him on the lips - a parody of the hospital scene in ‘The Descendants’.

The sequence also saw an appearance from teen star Justin Bieber spoofing ‘Midnight in Paris’. A tuxedo-wearing Bieber walked up to Crystal and said:  "What's up? I'm here to get you the 18-24 demographic. So how long do you want me to sit here for?". Indeed.

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Sammy Davis Jr. and Tom Cruise also showed up in the scene, the latter in a parody of 'Mission: Impossible - Ghost Protocol'.

Crystal then performed a song and dance number celebrating the nine Best Picture nominees.

Billy Crystal was seen as a safe pair of hands, but delivered a few risky-ish gags. Introducing Christian Bale, presenting an award, he warned the audience: "Be careful, you're in his eyeline." Bale famously berated a crew member who did just that on the set of 'Terminator Salvation'.

Talking about the impact of films, Crystal joked: “The movies have always been there for us. So tonight, enjoy yourself. Because nothing can take the sting out of our economic worries more than millionaires presenting themselves with little gold statues.”

He also quipped: "Please welcome a recurring dream of mine… Cameron Diaz and Jennifer Lopez." The pair were also presenting a gong.