Every member of the Actors Studio has been ordered to attend a meeting Thursday for the unveiling of a new code of conduct that defines sexual harassment and outlines how complaints must be handled.

The mandatory meeting was called after some students hired a lawyer, who is looking into suing the organization.

“Teachers have taken advantage of their students,” one source told me. “There’s a library where a lot of sex goes on.”

The studio, run for decades by the late Lee Strasberg, taught “method acting” to stars such as Marlon Brando, James Dean, Marilyn Monroe and Robert De Niro. Its co-presidents now are Ellen Burstyn, Al Pacino and Alec Baldwin.

Harvey Keitel quietly left the executive committee last year “because he was disgusted by the situation,” an insider said. Keitel couldn’t be reached, and the Actors Studio didn’t immediately respond to requests for comment.

The new code of conduct hints at bitter infighting, warning against “personal attacks . . . and anonymous campaigns, inside or outside the Studio, are never tolerated and will result in suspension or loss of membership.”

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