The Culper Ring worked to prevent crises and skirmishes between global factions and nations, prior to the events which form the basis of the series (namely the death of every man on earth save one). They are also alleged to have engaged in political assassinations and other extralegal 'dirty tricks' at the behest of various U.S. Presidents. While very little is currently known about the group, it is clear that agents were trained from a young age in a special school or operations camp. Once the initial training was completed, an agent then moved to field work under a senior agent. Their activities included the assassination of Patrice Lumumba, rigging the 1968 presidential election, and recovering the lost tragedies of Aeschylus and the Amulet of Helene. In 1977, Jimmy Carter restructured the group, resulting in the establishment of a hard-line splinter group, the Setauket Ring. One of the main characters in the series, known only as Agent 355, reveals (in issue 28) that her commanding agent, Agent 1033, trained her in close mentorship before they became involved in a romantic relationship. Each male agent is given a prime number to identify them.
Culper Ring agents are trained in a variety of self-defense and martial combat techniques. They are well-trained in the use of firearms, but are capable of defeating any opponent with a variety of methods. In issue 16, Agent 355 uses a telescoping rod to blind an opponent. In issue 29, she manages to break an opponent's neck, yet leaves her conscious so that she may interrogate her.
In the comic's final issue, which takes place sixty years in the future, an agent mentions working for the "Culper sphere." As she is taking orders from the president of France, as opposed to the United States, it can be assumed that the Culper ring has expanded into an international organization.