Checkmate, a division of Task Force X, is a fictional covert operations agency within the DC Comics universe. It first appeared in Action Comics #598 and proceeded to have its own ongoing title in Checkmate! (vol. 1). In the wake of events depicted in the mini-series The OMAC Project and Infinite Crisis, Checkmate has been re-chartered as a United Nations Security Council-affiliated agency and has its own new series, Checkmate (vol. 2).
The Checkmate organization was created by Paul Kupperberg and Steve Erwin, first appearing in Action Comics #598 in 1988. The precursor to this fictional organization was known as the Agency, first appearing in Vigilante #36. Harry Stein was appointed Valentina Vostok's replacement in The Agency's command position by Amanda Waller. Stein later sought out the most stable personnel available from the American and international intelligence and law enforcement communities to form Checkmate. His agency would field only the best-trained and well-equipped of agents, working under the strictest rules of secrecy. For the organizational structure of the re-organized Agency, Stein chose the game of chess as his working model.
Stein brought in Gary Washington (Knight One) and Black Thorn as Checkmate operatives, both of whom were his friends, and both of whom were introduced during his run on Vigilante.
Checkmate! was at various times involved with the other government agencies in the DC Comics universe, primarily the Suicide Squad, which resulted in the crossover "The Janus Directive". Checkmate! was canceled after 33 issues but the organization continued to appear, mostly in titles related to either the government or Batman.
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