There's always so much to unpack about a movie trailer: the stars, the plot, how much of the plot is being totally given away. But in many cases, the part of the trailer that sticks with you the longest is the music. Be it a pop song or a piece or orchestral score, it's the music that most often makes a trailer.

This Week's Trailer: 2 Guns,

This Week's Tune: "Watchtower," a Hendrix-cribbing hybrid creation by Devlin, featuring Ed Sheeran. Slightly more than a simple cover of "All Along the Watchtower," slightly less than a purely original creation. Original rap interludes weave into, around, and through the original, but the signature is still very much Jimi Hendrix's "Watchtower."

How Literal Is It? The original song is an epic whirlwind of ancient drama and preparations for warfare. The new verses are nonspecific boasts about coming up from nothing. The movie features two separate undercover agents working the same case, and each other. Not one sentence that I just wrote fits with any of the others, really. So I would think that "literal" doesn't have much to do with the song choice.

How Emotional Is It? The whole point of the 2 Guns trailer -- in fact the 2 Guns film -- is Bruckheimer/Bay-influenced action, with lots of bombast, a little humor, and ample opportunity to make the stars -- Denzel Washington and Mark Wahlberg as the rival law-enforcement agents -- look iconic and badass. The Hendrix licks get the iconic part down, certainly. Using the updated version, with its Brit-rapping and Ed Sheeran providing some sweet-sounding vocals, makes it all feel very modern and updated. Not the same old cop movie. How effectively it sells that premise will probably go a long way towards whether you want to see the movie or not.

How Definitive Is It? Ohhhhhh, not at all! Just because it's an updated version doesn't mean that the "All Along the Watchtower" guitar riff isn't one of the most everpresent music cues in all of entertainment.

Overall Trailer Tune Effectiveness: It depends on what you look for in your trailers. On one level, you want your trailer to communicate to viewers what to expect, and if you want viewers to expect the same kinds of thrills and action they've been enjoying with this genre for many years, this song does that quite well. If you're looking for something edgier, more innovative, promising something dangerous and new ... this is not the song to use.