There was hardly a cloud in the sky over Indianapolis on Wednesday morning when it started raining money.

In a moment that instantly tested the core of human morality, the definition of right and wrong, and the limits of acceptable risk, the back door of a Brink’s armored truck swung open during rush hour on Interstate 70, blowing bags of cash onto the highway.

There was money — $600,000, troopers estimated — everywhere.

Some bags tumbled onto the road and stayed intact — thousands of dollars, sorted and organized, just sitting there for the taking. Others ripped open, showering cash over four lanes of the interstate. On the shoulder, $20 bills gathered like leaves and formed piles in the grass off the highway.

Suddenly, the timeless hypothetical question became reality: What would you do?

A school bus driver knew what he would do, the police said. He pulled over on the highway, jumped out from the driver’s seat and grabbed some cash before driving away. So did four men in a white pickup truck who snatched an entire bag and then sped off.