An enormous force of aircraft swoop down on Pearl Harbor.
Even though surprise is total, the defenders manage to shoot down two of the attacking aircraft; Nagumo wanted to use the enormous number of surprise points on increasing his damage ratio, and figured that would be better than reducing the anti-aircraft fire. Not sure if that was the right decision.
The bombers concentrate on the carriers Lexington and Yorktown. They are both sunk, along with the Arizona and the Houston.

"Look at you - you have HORSES! What were you thinking?!?" - Paratrooper David Webster