Definition of 'Shock'

An example of Shock was in the opening scene of the film 'Children of Men'.

The opening scene we see a crowd being formed around a TV in a coffee shop, where we learn that the youngest person on Earth had died. We follow a young man out of the coffee shop, then we hear a sudden explosion and see the remains of what was the coffee shop. Here after we see a woman leave the coffee shop clutching a severed arm. This scene had shock because as an audience we weren't expecting the explosion.