The question really is, will it be called Die Hard 4: Die Hardest? Len Wiseman (Underworld: Evolution) has been tapped to direct the next adventure of Detective John McClane.
Aint it Cool managed to get a first look at the script and describe the plot as terrorists systematically trying to seize the U.S. technological infrastructure via a three-day plan. They will gradually step up malfunctions starting with traffic control systems, working towards economic markets, and finally shutting down key utilities like power and water to send America essentially into a modern Dark Ages.
As with other Die Hard films, the plot is a smoke screen for the real motive – money. So what’s McClane’s connection to all of this? His son, a cyber-thief who’s just been released from prison for stealing high security information, knows his former buddies are behind the massive plot. However, things go badly in their attempt to assist the government and the two end up on the run. No other characters from the other Die Hard movies are mentioned in the plotline.