Greg Addison was a high-ranking agent of the United Nations Security Council.
In 2011, he started having the Sanctuary Network secretly watched in order to find out the whereabouts of the Crixorum, a dangerous abnormal psychic from Hollow Earth. When his plan backfired into a bloodbath in Jakarta, he had himself appointed an inspector and led a team that investigated the Old City Sanctuary.
Eventually, Dr. Helen Magnus convinced him that she had sent the Crixorum back to Hollow Earth. As a result, he told her that the U.N was putting him in charge of the Sanctuary Network, otherwise all of its assets in the world would be frozen. To his surprise, Magnus threw him out and threatened that if he returned, she would have him eaten.