Bilbo vs. Gollum

You might expect the trailer to open with the King of Wakanda, but instead, we see Everett Ross (Martin Freeman) interrogating Klaw (Andy Serkis). According to director Ryan Coogler, the scene takes place in a safehouse in South Korea, and its purpose was to show how little outsiders knew about Wakanda (Ross, a CIA operative, knows little to nothing about the country).

We met Klaw in Avengers: Age of Ultron, in which the smuggler/arms dealer lost his arm when Ultron broke into his base. However, we don't know how much time has passed since then, and we don't know whether the Avengers captured Klaw at that time. We assume they didn't, since there’s shot in the teaser that could be from Klaw's capture scene. In that same shot, we see how formidable the Dora Milaje are.

So Klaw has no arm, but he’ll resemble the comics’ Klaw to a certain degree, since it was revealed that he'll use advanced Wakandan mining equipment as a sonic cannon.

What do you make of this? Did this heist take place before his capture or after Killmonger freed him?

We met Ross during Civil War, and his role in the trailer was to show how little the strongest and most capable intelligence agencies knew about Wakanda. So mission accomplished!