During Millennium's second season episodes Owls and Roosters, the Millennium Group is almost divided into two factions, which threatens to escalate into a civil war between The Owls (who believe in a scientific natural form of Armageddon) and The Roosters (believing in a religious apocalypse). Millennium Group member Johnston (of the Owls) developed a theory about a tear in the fabric of the universe; one that would reach Earth in sixty years. Lara admited she believed the theory, but would not join the Owls because of her persistent apocalyptic visions (which cannot be explained through science). The Old Man then joined in the discussion, explaining that a third party had been manipulating the Group in hopes of triggering its demise.

Later, the Old Man explained to Lara that in the waning days of World War II, Nazis began a secret project known as Odessa, in which high-ranking SS officers fled to countries south of the equator. One of these men, Rudolph Axmann, helped defeat their greatest enemy, communism, in the 1980s. Now Odessa had turned its attention towards the Millennium Group.

The alphabetical listing below includes all currently known characters who are identified as members of Millennium's Odessa organisation.