Mischa Barton was straddling two lanes

Mischa Barton may have been feeling nostalgic for her days on "The O.C." Like her character Marissa Cooper, the actress was caught being irresponsible with alcohol.

The 21-year-old was arrested in West Hollywood early Thursday morning for DUI, reports People.

Lieutenant Honings of the West Hollywood Sheriff's office said that the former "O.C." star was stopped at 2:46 a.m. when she was seen weaving between lanes and then making a turn without signaling. She was booked for driving under the influence of alcohol, possession of illegal narcotics and driving without a valid license.

By 10 a.m., she was released after posting $10,000 bail.

Barton is best known for playing Marissa Cooper on FOX's "The O.C." Last season, her character died in a car crash. Her film credits include "Notting Hill," "The Sixth Sense" and the upcoming Black Plague comedy "Virgin Territory," "St. Trinian's" and "Closing the Ring."