The Australian Threat Unit, or ATU, is an Australian government organization set up to research, combat, and contain the Inhuman Outbreak.
In late 2015 several individuals across the world underwent Terrigenesis during the Inhuman Outbreak. The result of this process was a new subspecies of humanity known as the Inhumans. Inhumans, who were unaware of their genetic potential for superhuman abilities, were surprised at their sudden development of abilities and as such, did not know how to control their powers. This led to many incidents across the globe as their enhancements manifested. The inadvertent destruction caused by Inhumans, along with public xenophobia, uncertainty of HYDRA involvement, and government security concerns about extraterrestrials, led to the formation of national containment units worldwide. These units, such as the ATCU and ATU, were tasked with countering and containing the outbreak, along with collecting Inhuman specimens.
As part of their mission, the ATU had captured an Inhuman by the name of Eden Fesi, who was held by the organization and subjected to medical and military experimentation. The actions of the ATU were highly classified, and only top officials within the Australian government were aware of their clandestine operations. One such person, Ellen King, attended a political symposium in Taiwan to coordinate a global response to the Outbreak. King traveled to the event with a document outlining the classified details of Fesi's incarceration.