Sigma Force

The SIGMA Force is a fictional division of the U.S. DARPA program. The chief operatives in SIGMA combine highly trained military skills with specialized scientific knowledge. The Force's purpose is to investigate and to secure sensitive information that could be a threat to the United States; its functions are a combination of counter-terrorism, research, and covert operations. Following the first book, Sandstorm (2004), the SIGMA Force headquarters moves into the sub-basement of the Smithsonian Institution in Washington, D.C.