This scene from S03E02 showed Margaery Tyrell's skills in manipulation and in playing the Game of Thrones. It started with her in front of Joff's crossbow, being questioned about her past marriage to a traitor. She carefully trod around this, acted like a typical lady and stated that the "subtleties of politics" were lost on her—when it's the complete opposite. It ended with her out of the way and taking hold of the lethal weapon, side by side with the King. A cunning show of power play.