The investigation into the disappearances of various, seemingly random people continues. With the help of Dum Dum Dugan, Tony finds the common thread between all of them; they all have a genetic resistance to the Extremis virus. This is also true of the individual who attacks Tony (who, deprived of his Extremis abilities, fights with an old set of armour), and is only defeated with the help of Doc Samson and Captain Ultra.
