These frames from Children of Men show exactly how when this scene opens, we think we're just watching people observing a television set. We don't works, because through to the front. When he does expect clive owen to push and looms into view, it's clear that he's made an entrance to the film. There are several ways to make your character strand out at this point. One is to give him more light than the other people in the scene. Another is to make sure that everybody who's on the same plane as him is shorter. The Children shots show this well. Everybody else on the front row is relatively short, so he towers above them, making it clear he's the hero of the piece