At his lab, Arcane monitors his manmade earthquake and Sunderland congratulates him. Arcane assures him that it's untraceable, just as a tremor shakes Arcane's lab. Graham reports that the pulse modulator hasn't shut down as employed, and Arcane blames the mishap on Graham when Sunderland demands an explanation.
Swamp Thing feels the tremor and realizes that it's not natural. He sinks into the earth before he can react. Swamp Thing lands in a cavern and realizes that the air is bad.
Arcane checks with his head technician, Sienna, who slaps him when he grabs her arm and demands an explanation. She tells him that they're refueling the pulse modulator and it's unstable, and she has 25 seconds to complete the process before the acid neutralizes. Arcane apologizes and gives her the dark particle spectrum key to complete the refueling. He tries to flatter her but Sienna reminds him that she's an engineer, not a concubine, and goes to work.
Will and Whitehead leave to buy Will a new truck. Once they drive off, Abigail comes out with their snack and complains that she missed them. The porch shakes briefly but only Abigail feels it. Tressa goes to repair the dock.
Another tremor shakes the cave that Swamp Thing is in. He finds the pulse modulator and discovers that it's tapped into the earth's core. Swamp Thing tries to unroot it but realizes that he's weakening because of lack of sunlight. Two guards attack him and Swamp Thing defeats them and drags them into an adjoining cave but his condition continues to weaken.
Arcane tells Graham that Sienna's idea to have female engineers in the underground is excellent. Sienna comes in and starts complaining, and Arcane tells Graham to shut up when he berates her. The engineer says that she wants full power transferred to the pulse modulator. Graham warns that the full load of acid will burn out the modulator, but Arcane agrees with Sienna and tells Graham to implement her instructions. Another tremor shakes the complex when he does so, but Sienna says that everything that comes from Arcane can handle full power.
As night falls, Tressa tries to pull out the rotting piers on her dock. The ground shakes and a timber falls on her leg, trapping her.
Arcane has dinner prepared for himself and Sienna, and covers over Tatiana's hibernation chamber with a cloth. Sienna comes in and Arcane talks about an oyster diver who fed him oysters when she brought them up. The engineer tells him that the last tremor should not have occurred, and Arcane hands her a glass of wine. She wonders what the challenge is in Arcane having everything he wants, and he kisses her. Arcane brushes the dishes off of the table , lies Sienna down on it, and blows out the candles.
Abigail hears Tressa's cries and goes to help, but is unable to free her. The river water is rising, and the phones and electricity are out. The newscaster announced that they're letting the water out of the reservoir.
Swamp Thing realizes that the smell is the acid that Arcane is using, and he placed the modulator underground to hide it.
Sienna comes in and accesses the modulator directly, triggering the self-destruct. A guard comes up and Sienna challenges him, and stabs him when he insists on calling in for instructions.
The next morning, Abigail is still unable to free Tressa as the water rises over Tressa's head.
Swamp Thing extends a vine into the ceiling and creates an opening to let the sunlight in.
Sienna goes to Arcane and suggests that they make the earth move again. They kiss and Sienna says that complex will melt down in eleven minutes. She draws a knife on Arcane and says that Woodrue paid her $1 million to kill Arcane and $2 million to destroy the modulator. Arcane dismisses Woodrue as a hack and fraud, but Sienna says that the destruction will finish off Arcane's reputation. The scientist pulls a knife of his own and says that the hidden metal detector told him about the knife. A tremor shakes the complex and Sienna frees herself. Evenly matched, the two of them fight.
Swamp Thing regains his strength and sees the self-destruct activated.
Sienna takes Arcane down and an alarm goes off as the sunlight and oxygen disintegrate the acid. She runs off goes to the self-destruct panel. Arcane follows her and warns her that the fumes will kill her, but Sienna insists that she can handle it and figures that he's bluffing. She collapses as the machine blows up.
The tremors free Tressa and Abigail pulls her to safety.
Arcane holds the dying Sienna in his arms, and she says that it was only business. Swamp Thing comes in and says that sunlight gives him life and destroyed the acid. Arcane promises to build it again, but Swamp Thing points out that it will take decades to synthesize enough accident. Furious, Arcane orders Swamp Thing out and looks at Sienna's body.
Later, Arcane calls Sunderland and tells him that Woodrue was responsible and tried to destroy Sunderland's trust in Arcane. The scientist excuses himself and then tells Tatiana that he knew Sienna was a spy and she could never replace Tatiana.
Written by Gadfly on Aug 2, 2017