But I had gradually evolved and organized another means of combating them. This consisted of a secret organization of super-assassins. In other words, I had elected to fight the devil with fire.

When an assassination was reported, my organization acted in the role of detective to ferret out the murderer. Then it acted as judge and jury and eventually as executioner. Its every move was made in secret, but over the heart of each of its victims an «X» was cut with the sharp point of a dagger.

We usually struck quickly, if we could strike at all; and soon the public and the assassins learned to connect that «X» over the heart as the mark of the hand of justice falling upon the guilty; and I know that in a number of the larger cities of Helium we greatly reduced the death rate by assassination. Otherwise, however, we seemed as far from our goal as when we first started.

Our poorest results had been gained in Zodanga; and the assassins of that city openly boasted that they were too smart for me, for although they did not know positively, they guessed that the X's upon the breasts of their dead comrades were made by an organization headed by me.

I hope that I have not bored you with this exposition of these dry facts, but it seemed necessary to me that I do so as an introduction to the adventures that befell me, taking me to a strange world in an effort to thwart the malign forces that had brought tragedy into my life.

In my fight against the assassins of Barsoom, I had never been able to enlist many agents to serve in Zodanga; and those stationed there worked only in a half-hearted manner, so that our enemies had good reason to taunt us with our failure.

To say that such a condition annoyed me would be putting it mildly; and so I decided to go in person to Zodanga, not only for the purpose of making a thorough investigation, but to give the Zodangan assassins a lesson that would cause them to laugh out of the other side of their mouths.