Continuity mistake: When Frank reveals himself to the public in front of a group of reporters and two former co-workers - when we first see him, you can see he is wearing a black button-up shirt that is buttoned all the way up, except for the top two, revealing that he is wearing his skull t-shirt underneath. (You can see the top of the skull peaking out.) But a few shots later, the bottom half of the shirt is completely unbuttoned (only one button is actually buttoned up), with him having no time or reason to do so between shots. In addition, when the bottom half half of the shirt is unbuttoned, you should be able to see the rest of the skull, but you can't. You can tell the skull just sort of stops midway down the shirt, revealing that he is wearing an alternate version of the t-shirt that only had the top half printed on it, so it would be just visible peeking out of the top of the button-up shirt.
Continuity mistake: When Howard Saint is in the limo after burying his son, he gives instructions to his best friend to kill Jack. His hair is wet and put back with gel. His friend says "all right", then we cut back to Saint, whose hair is now less slick. Cut away and back, and his hair is exactly how it was before.
Revealing mistake: When the Punisher's wife is driving madly away from the Saints with her kid, their Jimmy flips over and rolls, and we can see the gas tank has been removed. Also notice the vehicle is fully caged and we can see the pipe cannon go off underneath the vehicle as it flips the car, also visible as the car lays on its side.
Revealing mistake: When Saint shoots one of his henchmen for not taking care of his son, when Saint throws his gun on the body, the henchman jerks.






Answer: The song is "La donna é mobile" from the opera Rigoletto.