What is the main idea of the passage?

Because D$.$ B$.$ Cooper asked for four parachutes along with $$200,000$ in ransom money, he escaped before police could capture him.

In $1971,$ criminal D$.$ B$.$ Cooper hijacked a commercial airliner and secured a $$200,000$ ransom before parachuting out of the plane.

A famous mystery involves a citizen who hijacked a commercial airliner and held passengers and crew hostage for three hours.