There’s some brilliance in the simplicity of this prank video. While his friend is taking a shower in a public bathroom, the guy in this video manages to keep pouring new shampoo on his friend’s head. His friend never realizes that a trick is being played on him, and just keeps rinsing his hair, wondering why the shampoo never ends.
Then the kid who’s being tricked starts to doubt the shower’s effectiveness and keeps checking the flow of water from the shower head. This is a hilarious prank guaranteed to annoy, but not harm.