As the new Captain America: Civil War trailer opens, an roomful of superheroes watch footage of an alien invasion that decimated New York City.

As the Batman v Superman: Dawn of Justice Comic-Con trailer opens, a roomful of U.S. Senators discuss an alien invasion that decimated Metropolis.

To me, this is the most interesting thing about the big superhero showdown lumbering into theaters this spring. It’s not just that Marvel and Warner Bros. (owners of the DC library of characters) are about to square off at the box office; it’s that they’re about to square off at the box office with two movies about the exact same thing, namely the ideological divide between warring superheroes. In Batman v Superman, the Dark Knight (Ben Affleck) and the Man of Steel (Henry Cavill) do battle over the collateral damage caused when immensely powered beings beat the crap out of each other. Replace Bats and Supes with Cap (Chris Evans) and Iron Man (Robert Downey Jr.) and you’ve pretty much got the plot of Captain America: Civil War.

When both of these movies open (in late March and early May, respectively), they will surely diverge in lots of different ways. But at least in their trailers, there’s really just one big and very noticeable difference between Batman v Superman and Civil War: The time of day in each movie.

Critics and fans often talk about the “darkness” of Zack Snyder’s Man of Steel; the way its version of Superman doesn’t always save people, and even kills an enemy at one crucial moment. But at least in trailer form, Batman v Superman is literally one of the darkest superhero movies ever made. It seems like every scene is set at night, or in the rain, or at night in the rain. Just a few screengrabs from the various trailers:

It’s even nighttime when Superman heads back to Smallville for a pep talk from Ma Kent (Diane Lane)!

Captain America: Civil War’s trailers present a much sunnier interpretation of the same thematic material. In fact, there isn’t a single shot in the latest trailer that’s definitively set at night. Even the most intense moments take place in broad daylight.

The closest Civil War gets to a night scene is this shot of a stormy sea:

Civil War could come out in May with whole sequences not featured in the trailers all set at night. And while I tend to doubt it given Zack Snyder’s schtick, the opposite could be true of Batman v Superman (and there are a few scenes in its trailers set during the day, although most involve the destruction of Metropolis from Man of Steel). This doesn’t necessarily mean that Batman v Superman will be a darker movie than Civil War. But it does mean that it’s being marketed as a darker movie than Civil War.

Oddly, this is something one of these movies even seems to be addressing in its trailers. Several of the spots for Batman v Superman feature Lex Luthor (Jesse Eisenberg) referring to the battle between the two title characters in grand mythological terms. “Black and blue!” he hisses. “God versus man. Day versus night!

Lex is talking about Batman and Superman. But he might as well be talking about Marvel and DC, and the tactics they’re using to differentiate two similar looking movies.

Check Out a Gallery of Official Civil War Photos: