 It is later revealed that the symptoms of the mysterious poison are strikingly similar to those of a deadly biological weapon, called Nerve Agent S, developed by the Rocky Mountain Arsenal outside of Colorado as the ideal weapon for use on troops wearing gas masks and protective clothing.The agent clings to everything and is absorbed through the skin, resulting in almost immediate death.The weapon was eventually discontinued by the Army because it was as deadly to the troops deploying it as it was to the enemy.