Mischa Barton - Smokin' Hot?

In The Beautiful Life, she plays a gorgeous fashion model but actress Mischa Barton looked less than glamorous as she arrived on the New York set Wednesday.

With her hair scraped back, no make-up and a cigarette hanging from her lips, the 23-year-old looked almost unrecognizable.

Wardrobe Malfunction! Mischa Barton Bursts Out of Dress

But after spending some time with a team of make-up artists and stylists she emerged from her trailer looking fresh-faced and sporting a plunging green Herve Leger dress.

Before she started on the show the former O.C. star had a very public meltdown which resulted in a short stay at a psychiatric ward.

EXCLUSIVE: Mischa Barton Turns On the Charm With A Mystery Brit

But despite concerns from friends and family that she was rushing back to work too soon Barton remains positive and up-beat about her current mental state. She said: “I’m just very happy to be feeling happy again and back on top of it and not so worried about everything – it was just too much to handle.

One stay in hospital was turned into this huge ‘She’s lost her marbles’ thing, and people look at me like I’m instable and they should probably cross the street when they see me. I just had a bad time of year and now it’s allover and done with.”

VIDEO: Mischa Barton Blames Meltdown On Wisdom Teeth

Ironically in The Beautiful Life Barton plays a drug addicted supermodel Sonja Stone who is struggling to stay on top in the fiercely competitive fashion world.