This short video from the red carpet prior to the AFI Awards in 2006, captures Heath Ledger in what is known as a "Startle Reflex". As human beings we are born with only two fears - the rest are all acquired. These are the fear of falling and of loud noises.
As yet unbeknownst to the Mr. Ledger, Magda Szubanski who played Sharon Strzelecki in the television comedy show "Kath & Kim" (Australian version) - is putting on an act here. Many who were there as well as most non-Aussie viewers erroneously believed Szubanski to be a crazed fangirl.
Reflexes exist in for function and protection. In this instant you see Ledger's upper arms move close into his torso as the distal arm and hand reach up to protect the head and neck. Yet this is not body language - it is reflexive. This same movement can also be seen in the woman interviewing him.
As with surprise, shortly after the startle reflex, very often another emotion will rapidly replace it. Here that emotion is joy-happiness.
Ledger's forehead is relaxed, his eyelids are partially closed with a concave-up furrow in the lower eyelids. The upper teeth become quite visible with the bottom ones being covered.
One hint that Magda Szubanski's fainting was feigned - is that she covered her head immediately upon falling. If she were truly unconscious, she would of course not do this.
Ms. Szubanski exhibited several other nonverbal tells in the seconds prior to her "faint" which betray the fact she was acting. How many can you spot?
Nonverbal Communication Analysis No. 3349: Justin Trudeau, Stephen Harper, Sophie Grégoire, & Laureen Harper in Ottawa for Nathan Cirillo's Ceremony
Nonverbal Communication Analysis No. 2304: It Came from Outer Space - Russian Meteor Event over Chelyabinsk Don't Confuse this Reflex with Body Language
Nonverbal Communication Analysis No. 2782: Hillary Clinton dodges a shoe - Body Language ... and Not
Nonverbal Communication Analysis No. 3190: Taylor Swift's Body Language of Feigned Surprise