Night and her brother Fog were given their superhuman powers by German scientists in the days of World War Two. Hitler intended them to personify his message that those who opposed him in the conquered lands of Europe would disappear in the Night and Fog, and so he sent the pair to capture and kill various opponents of the Nazi's.
One such victim was to be "Emerald Ed" Reilly, who, since September 1939 had ensured production of ball bearings and other war materials had been particularly slow to leave his factory, because he hated the British. However, when the truth about German concentration camps and mass murder reached his ears, Reilly was incensed and did all he could to co-operate with the Allies. Hitler sent Night and Fog to change Reilly's mind.
Refusing to co-operate with the Nazi scheme, Reilly was thrown by Fog from a window high above ground level. Although his own daughter Danette (Firebrand) Reilly caught him, "Emerald Ed" had a heart attack and died in her arms. Meanwhile, Night and Fog were battling members of the All Star Squadron, and despite the heroes' best efforts the pair escaped. It is unclear whether they survived the Second World War.