An unnamed celebrity anonymously filed suit Tuesday against a woman who he claims is threatening to release a tape of them having sex unless he pays her $2.5 million. Identified only as Doe in the Los Angeles Superior Court complaint, the plaintiff wants an injunction preventing the defendant, her former attorney and a sex tape broker from allowing anyone to view the tape or duplicating it. He also wants the video and any copies lodged with the court pending the outcome of his lawsuit. The woman, identified in court papers as Elizabeth Ruiz, could not be immediately reached for comment.