Justice League Final Trailer: 10 Plot Points It Reveals

6. An Invasion, Or Something Darker

At one point during the trailer, Diana speaks of an "invasion". At another, Bruce suggests that maybe it's "something darker". Although the two scenes are different, the editing makes a clear link between the lines, and speaks to what we might be able to expect from the film.

The Parademons are going to be the first line of attack on behalf of Steppenwolf (and Darkseid above him), which is the 'invasion' aspect, before we get into what's really happening: the arrival of Steppenwolf, the hunt for the Mother Boxes, and their power being turned over to the forces of evil. We at least know that Diana is working in London, and we see British police in this trailer, which hints at how she comes to realise what's going on and why she's so committed to the League.

The invasion line, however, also hints at the history lesson we're going to see in the movie. With Robin Wright set to appear, we're going to be getting a flashback of the major conflict between the humans, Amazons, and Atlanteans against the Parademons. The ancient battle led to the Mother Boxes being scattered in the first place, and there's a chance that's what Diana is recalling here, with the fight itself likely being shown in the first act of the movie in order to establish the mythology and the stakes.