Twitter trolls

Caution! The celebs who are wary of Twitter

Watson is playing the lead role in The Circle, the film adaptation of Dave Eggers's novel about an all-seeing tech corporation.

She plays a graduate who joins Hanks's company and soon finds herself joining an experiment that pushes the boundaries of privacy and ethics.

Watson said at the New York premiere: "For my sanity, I cannot, I just cannot even go there (reading comments)."