On the basis of research conducted after World War II which found that only 15-20% of men actually fired their weapons at the enemy and of those only 2% aimed to kill, Grub Smith meets leading military and academic experts to look into why humans are actually reluctant to kill and how they can be made to. He undergoes infantry training.

Grub Smith looks at attempts by the US army to develop a force of super soldiers, and some of the methods employed to try and attain that, including combat training using "simunition".