Actress Sally Field was arrested in New York City while making dramatic Tv movie Sybil in 1976 because passersby thought she was mentally unstable.

The Oscar winner stayed in character in between takes and her multiple personality disorder actions were so convincing one concerned onlooker reported Field to the police over concerns she was deranged.

The 66 year old, who was just method acting, was taken into custody for an evaluation and Field admits she was mortified.

She tells U.S. Tv host Jimmy Fallon, "I don't leave character. I am a method actor, but I hide it because people will think you're weird if you're in a corner sort of mumbling to yourself.

"I did this thing... called Sybil and we shot a lot of it on the streets of New York... And we were sort of between shots... and someone called to have this very strange and obviously very disturbed woman arrested - and it was me.

"I was walking around the streets and someone reported me to the police... (Someone) had to come get me (and bail me out)."