This Means War aka The Knight's Tale (for Oct. 2nd prompt)

In "The Knight's Tale" from The Canterbury Tales, cousins Arcite and Palamon both fall in love with Emily, and their competition for her causes great strife between them, including a duel.

In This Means War, two best friends and fellow spies fall for the same woman and decide to ignore their friendship and use awesome spy techniques and explosions to battle it out for her love.