Barry shelters street orphans Terry and Cory Cohan, who have stolen the backpack of a recently murdered journalist, Philip Sullivan, containing Sullivan's research on a highly addictive synthetic drug known as "Blue Paradise", developed by notorious drug designer Beauregarde Lesko.

In the 1950s, Central City's guardian was Desmond Powell, who fought crime as "The Nightshade". His nemesis, a criminal mastermind known as "The Ghost", is believed to have died after a confrontation, causing a guilt-stricken Powell to retire. However, the Ghost has in fact preserved himself in suspended animation and resurfaces in the 1990s, where he hijacks Central City's power grids and holds the city for ransom, forcing Powell to return to action and join forces with the Flash.