New York, October 24, 1907. A newsboy (Joseph Ryan) announces that the great financier, J.P. Morgan (Bob Laine), has saved the city and the country from ruin by almost single-handedly taming the economy after the stock market crash of 1907. Morgan himself appears to the cheers of the crowd, buys a paper and heads to his palatial home. Once inside, he is startled by the appearance of The Black Dragon. Leading the Angel of Doom to a secret section of the house, Morgan shows him the newspaper and announces, "It all went according to plan!"

Meanwhile, in Pittsburg, PA, the electrical tycoon and inventor, George Westinghouse (Ian W. Hill), walks home in a daze, having just signed his massive business holdings over to Morgan to avoid financial ruin. He is nearly run down by a motorcar when he absentmindedly steps into the street but is pulled to safety by Brother Francis (Randall Middleton). Westinghouse thanks him but declines his offer for spiritual solace. As the tycoon walks away, Brother Francis pointedly recites from the Book of Revelation a verse about a great earthquake sent by God, stopping Westinghouse in his tracks.

After the Penny Dreadful title theme ends, the episode proper begins in the New Jersey laboratory of the great inventor, Thomas Edison (Tom Reid). It is May 1909 and Edison is watching the dailies from his "movie," Frankenstein, when his old arch-rival Westinghouse enters. The two immediately begin a verbal sparring match, first over their knowledge of Mary Shelley's novel of misapplied science and then the rehashing of the AC/DC wars that found the crusty inventor and the mild-mannered tycoon fighting each other for control of electrical power in the late 19th century. Westinghouse ends the argument by getting to the point of his visit and hands Edison a stack of cards - each with a date and place following the phrase, "God abandons," and an image of a black dragon on the obverse sides. Edison denies having seen them before or knowing about a "Black Dragon." Westinghouse then hands a similar card to Edison - it is an invitation to a meeting held in San Francisco in 1906 and Westinghouse demands to know why Edison didn't attend.

San Francisco, April 17, 1906. At the Palace Hotel, Carter Newbanks (Joseph Ryan), an assistant to J.P. Morgan, is thrilled to run into his old Pittsburg buddy, Edgar White (Randall Middleton), an assistant to Westinghouse. They compare the generosity of their bosses, the cars they get to drive and the girls they have back in their hometowns. Both confidentially admit that they are under orders from their employers to keep quiet about their presence in the city and the two young men muse over the nature of all the secrecy. They agree to sneak off to some saloons later once they escort their employers to their strange, secret event.

Back in the New Jersey lab, Westinghouse describes to Edison how he arrived at the mysterious event wearing a white mask that was provided for him. We flashback to the secret meeting as Westinghouse follows other masked men down a corridor into a candle-lit basement and sits down to a private performance by the world's greatest performer, Enrico Caruso. After the performance, one of the masked men takes the stage and enraptures the audience with a sinister tale. According to the man on the stage, he had been visited by an Angel who had told him that God had abandoned the world, setting into motion a series of events that would ultimately lead to its destruction in the year 2012. The man informs the masked men in the room that they are the most powerful men in the world and only they can unite to help the Angel save the Earth from its doomed path and return mankind to God's good grace.

The room of men is transfixed by the speaker's awe-inspiring words, but the reverence is shattered when the newspaper magnate, William Randolph Hearst (played by Trav S.D. in Episode 5), stands, removes his mask and recognizes the man on the stage to be none other than the great orator and politician, William Jennings Bryan, the bible-beating Democrat who had twice failed to be elected President. With the spell broken, the men erupt in laughter and remove their masks, revealing that they are indeed a collection of the most powerful men in America, including J.P. Morgan, John Jacob Astor, Andrew Carnegie, John D. Rockefeller, Henry Clay Frick, Cornelius Vanderbilt and William Howard Taft (Roger Nasser), to name a few. Only one man remains seated, refusing to remove his mask: the creature hiding in the shadows that we have come to know as The Black Dragon!

The men abandon Bryan and return to the street as the morning light breaks over San Francisco. As they chat, the Black Dragon appears, passes through them and makes a powerful sweep of his hands toward the ocean. The men watch as in the distance the Great San Francisco Earthquake of 1906 roars toward them from the ocean. The Black Dragon disappears as they are knocked to the ground by the massive tremors while buildings crumble around them and catch fire.

After the earthquake, Westinghouse looks about in a panic. Taft comes to him and says that a friend of Hearst's (Cyrus Pierce, who we saw murdered by his own daughter, Abigail, in Episode 5) has arranged for a private train out of San Francisco, but they have to leave immediately. Westinghouse is distraught that he can't find his assistant Edgar, but ultimately abandons him and heads for the train. Morgan tells Taft not to mention any of this to Teddy [Roosevelt]. As the men leave the city in secrecy, in another part of San Francisco, Carter Newbanks carries the dead body of his friend Edgar through the rubble, puts him down and weeps as the sounds of chaos continue behind him.

We return to Edison's lab as Westinghouse finishes his unbelievable story. He tells Edison that the men, convinced by the earthquake that godlike forces are indeed at work, eventually came back together and formed the Alliance of Tomorrow, dedicated to preventing the end of the world.

Westinghouse tells Edison that after the financial crash of 1907 - when he lost control of his company - the Alliance ceased to contact him, but he is happy to be free of them, as he has heard rumors that the Alliance is now involved in black magic and blood rituals and are even supposedly building a time machine. He also tells Edison that after the crash, he was approached by a priest (Brother Francis, who we met in the prologue), who revealed to him that the Jesuits are also interested in the Alliance, using their scientific observations to follow this evidence of End Times.

Westinghouse is curious why Edison was not invited to that fateful meeting since he is obviously the more famous electrical inventor. The two determine that J.P. Morgan, who took over Westinghouse's company, among many others, had used the crash to take the money and power from members of the Alliance that were suspected of losing faith and could not be trusted with their secrets. They were not interested in Westinghouse as an inventor at all - they just wanted his money.

Edison asks Westinghouse who else he has told about the Alliance - his wife, family? No. He only told Brother Francis and now Edison, because, though they were enemies, the two men are very much alike, and he knew Edison would understand. The two old rivals share a quiet smile, then Edison stands and tells a story of how years ago he convinced the State of New York to execute prisoners using Westinghouse's AC power by bringing in large animals and electrocuting them. All Edison had to do was get them to stand on the metal plate in the center of the room - right where Westinghouse is standing.

Suddenly, Edison throws a switch on the wall and Westinghouse stiffens in place. Smoke simmers from his clothes. Foam drips from his mouth. His eyes bleed. Finally, Edison opens the circuit again and Westinghouse collapses to the ground, dead. Edison sits and pens a letter to William Jennings Bryan, telling him that "G.W. came out to my lab and started telling me all about your little club. Don't worry. I took care of it. T.E." Edison puts the letter in an envelope, seals it, turns on the projector and calmly continues to watch Frankenstein.

Epilogue. It is four months later, September 1909. Edison sits in his lab, his ear to a phonograph playing a record. From his ear he removes the hearing aid of Robert Ford (which Detective Leslie Caldwell mailed to him in Episode 3), amazed that, after being almost deaf for 50 years, he can finally hear.

Then, with a burst of familiar music, in walks The Amazing Viernik (Fred Backus), bragging to "The Wizard of Menlo Park" that he has become an expert in code-breaking over the summer, and now that Viernik can read Mister E's coded journal (stolen in Episode 3), he knows that it was Edison who invented the Great Switcheroo. Viernik raises a pistol, points it at the old wizard and says, "And now you're going to make one for me."