Saw 3D trailer and structural timeline

Equilibrium: Establishing shot of buildings
Moment of disequilibrium: At 19 secs the entertainer's hand is stuck in the machinery
Disequilibrium continues: At 34 secs a man screaming with blood and another at 40 secs is tramped in a cage and hung in the air, the audience is tied to their chairs in the cinema.
Tone cards: At 57 secs "Will you survive till the end?" creates discomfort of safety and conjures fear
Last shot: At 1.16 secs the actress is tied and in front of a moving machinery/ride which subverts audiences reactions as it moves toward them instead this creates terror and presents the powerful 3D effects.