1 Hitchcock: Crowd Scenes, Heroes and Villains

The  duel between  the hero and villain/adversary is often in front of ignorant crows.

39 Steps, political rally

Saboteur, charity dance

North By NW, auction; observatory

Saboteur: hero tries to snatch of Nazi agents and to escape, but the scene is a great hall with guests, so they all have to observe rules of social etiquette.

The actions have to to be in accordance with  rules of social game

Crowd has to be kept ignorant as to the true stakes

(S. Zizak, p, 215).