There is a lesson here, tell me if you know what it is...

The farmers see a crowd of people. A samurai has gone to the river's edge to be shaved by a monk.
A man with a moustache and a sword pushes his way through the crowd and squats scratching his chin. (It's Toshiro Mifune)
A handsome, aristocratic young man asks someone what's happening. A thief is hiding in a barn. He is holding a baby hostage. The samurai has asked for monk's robes and two rice cakes.
The samurai puts on his disguise. He feels Mifune watching and turns. His eyes are black in a white face on a black screen. Mifune stares blankly back. The samurai's eyes are black in a white face. Mifune scratches himself. The samurai turns away. He turns back and looks at Mifune; his eyes are black, his face is white. He turns away and goes to the barn.
Mifune sits on a stump close behind him to watch.
The samurai tells the thief he has brought food, tossed the rice cakes through the door, and follows.
The thief runs from the barn and falls down dead.
The samurai drops the thiefs sword in the dirt.
The parents of the child rush forward to take it.
Mifune runs forward brandishing his sword. He jumps up and down on the body.
The samurai walks off without a backward look.