Thousands of years ago, the Kree Reapers were tasked with experimenting on various alien races in order to produce bio-weapons for the purpose of war. One of the planets they have arrived on was Earth. Among them, there was a Mayan hunter who they then proceeded to experiment on, by giving him their blood, and engineered to lead an army. Though they were intended to fight for the Kree, the leader of the army led them into a rebellion against their creators, and eventually banished them from Earth. They were then frozen, and put into a containment vessel that would take them back in response to a beacon.
Return to Earth
In 2016, upon the activation of the beacon in Union City, the Kree Reapers arrived back on Earth, descending within their pod and began hunting for Inhumans. Splitting up, one of the Reapers proceeded to attack and kill Alisha Whitley. The other Reaper, however, came across Holden Radcliffe. He was then suddenly attacked by Daisy Johnson, who proceeded to break his spine. This incapacitated him, albeit without killing him, allowing Radcliffe to safely drain his blood, a key component for the creation of the Absolution Virus. However, Alphonso Mackenzie destroyed the Kree with a Splinter Bomb, so as to stop its DNA from being harvested by Radcliffe.
Meanwhile, the Kree Reaper that previously killed Alisha Whitley found and confronted Hive inside a church. The Reaper noted that they should not have chosen him to lead the Inhumans as he attacked him. Although Hive was able to use Grant Ward's training to dodge and deflect the Reaper's attacks, he could not physically overpower the Reaper. When the Reaper began beating him down and claiming that he and the Inhumans were a failed experiment, Hive respond him that "sometimes the greatest miracles happens by accident", before using his powers to dissolve the Reaper's skull before dropping its corpse on the ground. Hive later removed the Kree's heart and use his blood for the creation of his virus.