The Enchantress, a Magical being born in 4,357 BC escaped her prison when Dr June Moone open the relic she was trapped in and took over her body. A.R.G.U.S. found Dr Moone and studied the mystery behind the Enchantress' powers, which were linked to her heart. Director Amanda Waller had the heart and carried it on her person once it was found and blackmailed the Enchantress into doing work for A.R.G.U.S., causing pain to the Enchantress by attacking her heart.
Colonel Richard Flag, Jr. was tasked with over seeing June Moone, and Waller manipulated the two into falling into a relationship together. The Enchantress became aware of the feelings Moone and Flag had for each other. Taking over Moone's body while asleep, Flag threatened the Enchantress but began giving him visions of Moone on her death bed, so he dropped his weapon and allowed the Enchantress to teleport away.
The Enchantress went to get her heart from Waller but a fail safe insert onto the briefcase didn't allow her near it. She instead retrieved her brother Incubus from the relic he was trapped in, and took him to Midway City Train Terminal where he could find a host and grow his strength. Incubus then began attacking civilians and gaining his strength, which alerted the Midway City Police Department and the United States Armed Forces who began plotting to take out the magical creature.
After being alerted to the threat posed in Midway City, Amanda Waller dispatched Flag & Dr Moone to the Train Terminal along with a team of US Navy SEAL's to plant a bomb underneath the Train Terminal in the subway, which was flooded and blow it up along with the magical being.
The Navy SEALS planted the bomb and set it to charge, while Flag escorted Moone towards the being to transform into the Enchantress to fight the being, not knowing she had secretly released it when Flag let her escape. Moone transforms into the Enchantress who immediately teleports away to her brother.
Flag informs Waller who begins violently stabbing her heart, which begins to severely weaken the Enchantress. Her brother Incubus transfers half of his powers to her until they retrieve her heart upstairs in the Train Terminal. The two then begin constructing a magical machine, that will build up until it destroys all the armed forces around the world so nothing can oppose them from ruling the Earth.
Flag and his team pull and out and stop the bombs detonation and resort to another plan. Waller has her Task Force X initiative approved and begins recruiting Super-Villains to do dirty black ops missions for the greater good of America. Flag assembles the Task Force X team, Deadshot, Harley Quinn, Captain Boomerang, El Diablo, Katana, Killer Croc and Slipknot. The team prepare at Midway City International Airport before flying into the battle, along with 2 teams of US Navy SEAL's in Boeing CH-47 Chinook's. The Eyes of the Adversary, former army and police personnel transformed into mindless beings by the Enchantress and Incubus, start firing at the 2 Chinooks on approach, catching the one containing Task Force X sending it crashing into the city centre. The team survive and meet up the second team, and make their way through the city, coming across previous battle grounds such as Midway City Square.