When releasing a film to the public, the film's score is usually the very last thing to be completed. This means that there will be enough finished scenes to make a trailer, but no soundtrack yet. What's a studio to do? Slap in some music from another film, stock music, or even a pop song, that evokes the general mood they're going for, that's what. Licensed music made entirely for trailers by groups like Two Steps From Hell and used to advertise several unrelated products is not an example of this trope. Examples of Recycled Trailer Music include: