What is SD-6?
 

SD-6 is an enemy of the United States.

Masquerading as a "black-ops" division of the CIA, it has lied to its lower level agents, since its formation over ten years ago. Our heroine, Sydney Bristow, is an agent who has learned of the deception.

As one of twelve branches of the Alliance — a private association of international organized crime — SD-6 trades in industrial intelligence, weapons, medical technology, military secrets and computer advancements all in exchange for profit. "SD" is Alain Christophe's term: "Section Disparu," Latin for "the section that doesn't exist."

Internally, SD-6 declares its mission as: "The retrieval and study of intelligence, both military and industrial, throughout the world, that is critical to the survival of the United States of America." Externally, SD-6 has a dangerous, but silent, presence.