I am. HandsUp.
A cocky, loud declaration from a criminal who thinks they're the main character. It means 'I'm not scared, and I'm about to make you regret your life choices.'
"I am. HandsUp.", Said by a kid who just robbed a convenience store and was still wearing his pajamas.
"I am. HandsUp.", Said by a guy who tried to steal a cop's badge and got caught mid-sprint.
"I am. HandsUp.", Said by a kid who thought he was in a movie, but the cop just laughed and gave him a ticket instead.