Mischa Barton's Late Night in London

Mischa Barton sports a Missoni mini-dress as she heads out for a busy night in London on Thursday, hitting up hotspots Mahiki Club, The Cuckoo Club, Fifty Casino and Lebanese restaurant Maroush .. all in one night!

The former O.C. starlet toted around her recent fave Gucci Indy Bag.

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