How easy is it to kill in battle? War footage and Hollywood-style dramatisations of battle abound, showing men killing each other. But what is it really like to take someone's life? Most young men are sure that if it came down to it they could kill for their country. But when British comedian and journalist Grub Smith hears about shocking research that seems to turn accepted thinking on its head, he decides to investigate. To find out the truth, he undergoes infantry training and meets leading military and academic experts.