In this section we like to explain how a particularly literary work fits into one of seven basic plots; the problem here is that Mr. John Milton has made the task difficult, actually nearly impossible. At first, we thought Paradise Lost should fall under The Quest plot, you know the Lord of the Ringsh type story where a group of characters set out to achieve something and have to fight a bunch of monsters on the way? Well, that sort of works, except our "hero" is more of an anti-hero: Satan. He wants to ruin Adam and Eve, and he confronts various obstacles, etc. At the end, he achieves his goal, but he doesn't live happily ever after in the same way that the hobbits do.
So, then we decided, well what about tragedy? That sort of works. Adam and Eve suffer pretty badly in the poem, but they're not tragic characters in the same way that Macbeth and Othello are. But then we said, "Well, what about Satan"? He fits the tragic character role OK (his tragic flaw is pride), but the thing is we don't really feel sorry for him the way we do for other characters. Or rather, when he is turned into a snake in Book 10, we don't really feel the kinds of conflicting emotions that we do at the end of Romeo and Juliet.