Why is the film called "Knight and Day" if neither of them are named either "Knight" nor "Day?" Shouldn't a title like that be a clever bit of word play? Unless he's an ACTUAL knight of some kind. Is he Ned? Is Tom "Day" Cruise a Knight in this film? And if not -- or even if so, really -- is the title referenced in the script? If so, how do they explain that? Does Cameron Diaz call Tom a knight? Do the writers not understand the significance of the letter "k?"

I cannot watch this film until I get an answer on this.

He is not a knight, but I think maybe one of his aliases might be Knight? Also, for like two seconds they show that the perpetual energy thingy is housed in a little metallic toy knight.

Also, some of the scenes take place during the day.

They could have called the movie "Cars and Explosions," which would have been a more accurate title.