Continuity mistake: When the Jesuit tries to kill King Louis, Louis grabs a long bladed knife and stabs the Jesuit in the chest, but when the camera pulls back, the knife is gone, and no one has made a move to pull it out of his chest. Only the blade that D'Artanian threw at him is there.
Continuity mistake: When the guards come to take Elizabeth away in the beginning, before she is queen, Lord Dudley has his back to the camera and is saying goodbye to her. You can distinctly see the clasp of a necklace on the back of his neck, but in the next few shots, there's nothing there.
Continuity mistake: When Shane first gets into Studio 54, he is told to take his shirt off. He pulls it over the top of his head. Then he walks in holding it and even though he never unbuttons it, it is somehow unbuttoned when he puts it on again.