Ellen was a police officer in Satellite City. She was stabbed by a criminal, and was therefore able to see the Parasites, which are energy beings who feed off the pain of the dying.
While working for the police, she was also secretly working for the Myishi Corporation to study the parasites. She befriended a cadet named Stefan Bakshir and his mother. She placed a bomb in Stefan's car, hoping to attract the parasites, and ended up killing Stefen's mother and turning Stefan into a Spotter.
Stefan started a group called the Supernaturalists which hunted the parasites, as he thought they were malicious. Whenever they "killed a parasite", Ellen was able to capture and study it.
Ellen had the Myishi corporation capture the Supernaturalists. She told Stefan that he was actually helping the parasites multiply. She then gave him a bomb to neutralize the parasites, and told him to find their nest to kill them all.
After Stefen set off the bomb, Ellen was able to capture all of the parasites. She planned to use them to create a clean energy machine for the Mysihi corporation. However, when Stefen found out that the parasites weren't malicious, he confronted her. She had the Supernaturalists captured. However, Cosmo helped the group escape so she shot Stefan. She told them her plan, and the Supernaturalist secretly recorded her confession and released it. Stefen used his last Strength to grab Ellen. She ordered a sniper to shoot him, but Stefen caused the bullet to miss and hit the glass containing the parasites. The parasites escaped and Ellen was seriously injured.
Later, Ellen was healed. The Myishi Corporation blamed Ellen publicly for the incident, and sent her to work in a facility in the Arctic.