Washington, Aug 5 : ''The O. C.'' actress Mischa Barton has been overheard ''''talking frantically'''' into her phone about having a stalker.

Barton was recently placed under involuntary psychiatric hold in Los Angeles'' Cedars-Sinai Medical Center.

She was apparently talking about the stalker while she was at New York''s Sant Ambroeus restaurant on August 1, reports Contactmusic.

A source told the New York Post newspaper: "She was upset and talking frantically into her phone about having a stalker.

"Her friends were trying to console her, but she went outside and chain-smoked cigarettes."

Meanwhile, in an unusual coincidence, the 23-year-old star plays a teen stalker in new film ''Homecoming''. (ANI)