There is a young man, different from other young men. Ancient prophecies foretell his coming, and he performs miraculous feats. Eventually, confronted by his enemies, he must sacrifice his own life—an act that saves mankind from calamity—but in a mystery as great as that of his origin, he is reborn, to preside in glory over a world redeemed. Tell this story to one of the world’s 2 billion Christians, and he’ll recognize it instantly. Tell it to a science-fiction and fantasy fan, and he’ll ask why you’re making minor alterations to the plot of The Matrix or Superman Returns. For reasons that have as much to do with global politics as with our cultural moment, some of this generation’s most successful sci-fi and fantasy movie franchises follow an essentially Christian plotline. Benjamin A. Plotinsky
I would disagree in that I do not think the reason is substantially political or cultural. I believe the reason is that truth is inherently interesting even if it's only true on an allegorical level.