The novel chronicles the founding of the Galactic Patrol by Virgil Samms, the first sentient being in our cosmos to wear the ‘Lens’, a unique badge of authority which is actually a form of ‘pseudo-life’ that grants telepathic powers to the defenders of Civilization. First Lensman picks up more or less where Triplanetary left off. The story follows the doings of the ‘First Lensman’ Virgil Samms. The Arisians know that he is incorruptible, a paragon of bravery and virtue, so they have chosen him to be the first entity to wear the ‘Lens of Civilization’.
Samms has a dream. He wants to establish the Galactic Patrol to protect civilization from the forces of evil for which he needs to have a reliable (unfakeable) symbol to identify its members. He is guided by one of his trusted subordinates to Arisia, a previously unapproachable planet, where he is greeted by a benevolent and telepathic Arisian who presents him with a ‘Lens’. The Lens is a device that can only be made by the Arisians and that can be worn only by the person that it is exclusively attuned to. It gives its wearer the ability to communicate telepathically with any being or animal with a mind, as well as other powers.