Captain America: The Winter Soldier had its first official trailer go viral this week (24 Oct.) and whilst it gives us a reasonable look at what we can expect from the the return of Chris Evans as the first Avenger, there may have been certain elements that you could have missed in the action-packed preview.

Captain America
The Winter Soldier trailer leaves plenty of questions

We get to see plenty of Scarlett Johansson as Black Widow and Samuel L Jackson returning as Nick Fury. In all it looks as though the film has a strong S.H.I.E.L.D. presence, but this doesn't give us a great indication of what the film might offer. As for the potential bad guys, it looks as though Robert Redford might have a few sinister ideas up his sleeve and the masked badass we see here and there might be his accomplice, but what does it all mean?

Lets start with the name, The Winter Soldier. In the comics, 'Bucky' Barnes initially serves as the Captain's sidekick, but decades later he made a reappearance in the comics as The Winter Soldier, brought back to life after following his wartime demise. The Captain make numerous remarks about his "friends" in the trailer, so could we see Bucky in the new film, perhaps in a sinister capacity? Bucky also becomes the seond Captain America following the presumed death of Steve Rogers, so could we have an interesting plot twist here?

One person we actually get to see in trailer is actor Frank Grillo, who goes by the name Brock Rumlow in the film. The S.H.I.E.L.D. agent also goes by the alter ego Crossbones (in the comic at least), who just so happens to be one of the Captain's major enemies, up there with the Red Skull in terms of dastardliness and determination to kill the Captain. He serves as one of the key players in the assassination of Rogers in the comic, so maybe thats what the operating scene is all about?

Considering that we see the Capt. and Black Widow looking into the operating room, probably not, but it could be Nick Fury who is under the knife, which is another interesting plot device. Whatever happened to Nick, or whoever it is in the operating room, will probably have a defining role in what happens in the Marvel movie universe and not just the Captain America film.

Captain America: The Winter Soldier opens in theaters on 4 April, 2014.