Here in is this poster we see a long shot of the trio looking very cautious and worried , this shows the audience that they expecting something bad to happen. We can see from the slight glow around them that they are honorable, innocent, and are set out to defeat the evil ahead. The tag on the poster is 'There's no place to hide' and the trio show this very well. They're facial expressions show that they are not safe, and that indeed there is no where they hide.
Their dress code is very formal, and shows the audience that they are growing up. It could also mean that they have been interrupted from an important social event because of the evil forces attacking them, or they think someone is after them. This is where the tag on the poster relates to the trio once again, they thought they were safe at social gathering, but in reality, no where is safe for them.