1882. After the death of her father and accompanied by Peggy Scott, Marian Brook travels to New York to live with her aristocratic aunts, Agnes van Rhijn and Ada Brook. Meanwhile, determined to break into society, ruthless tycoon George Russell and his ambitious wife Bertha move their family into a lavish mansion across the street and prepare to throw their first soirée.

Tom Raikes’ visit to New York delights Marian but worries aunt Agnes. An increasingly desperate Peggy seeks legal advice from Mr. Raikes, George takes steps to further his latest business plans, Oscar van Rhijn homes in on young Gladys Russell, and a charity bazaar becomes the source of a dramatic stand after Bertha is slighted.

An unfortunate development finds George’s new rail station under threat. Despite Agnes’ warnings, Marian continues to see Mr. Raikes, who lays his ambitions bare. Peggy learns that a publisher is interested in her stories. At a talk given by Clara Barton, Ada reunites with a childhood friend. Oscar grows attached to his plan, while Jack invites Bridget to a show.

In the aftermath of a tragedy, George makes a deal to help Bertha. Peggy gets an assignment from publisher T. Thomas Fortune, but a dinner with her parents ends on a sour note. Marian learns more about the mysterious Mrs. Chamberlain. Bannister's visit to the Russell house has a lasting impact on the staff. Bridget shares her dark secret with Mrs. Bauer.

George and Bertha extend an invite to a young man who's piqued Gladys' interest. After charming Mr. McAllister, Bertha accompanies Marian and Aurora to hear Clara Barton speak in Dansville. There, Peggy works on her article and shares the story of her first love with Marian, whose interest in Mr. Raikes continues to grow. Oscar crosses paths with a vengeful Turner.

Bertha goes all out at a luncheon to impress Mr. McAllister, enlisting the help of Bannister — who rubs Church the wrong way. George fights to protect his public image, while Agnes’ status quo is disrupted. As Marian debates her feelings, Mrs. Chamberlain makes her an offer. Gladys bonds with a new friend. Armstrong intensifies her campaign against Peggy.

As the city buzzes over Edison’s electricity demonstration, Bertha plans a picnic that involves Mr. Raikes — but not Marian. Agnes entreats her niece to protect the family’s reputation. George prepares for a legal battle as he bristles over Larry’s career ambitions. Bannister plots his revenge. Turner gets an unwelcome surprise.

During her first visit to Newport, Bertha follows Mr. McCallister’s lead but is soon reminded of her place. Oscar’s pursuit of Gladys is threatened by a familiar presence. George gets his day in court. Worried about Armstrong’s interference, Peggy reveals her past. Marian makes a decision about her romantic future. Bridget follows Jack across the city.

As Marian prepares to embark on a new adventure, Ada and Aurora rush to stop her before it's too late. With Gladys' debut ball fast approaching, the clash between Bertha and Mrs. Astor has consequences for all of New York society. The discovery of a shocking letter changes everything for Peggy. Baudin lays out his double life.

On Easter Sunday, Agnes informs Ada, Marian, and Oscar of her nephew Dashiell Montgomery's imminent arrival in New York. In need of a change after an emotional visit to Philadelphia, Peggy asks Marian about returning to 61st Street. Meanwhile, Bertha sidesteps Mrs. Astor to support the Metropolitan Opera House, and Oscar begins courting Gladys once again.

After giving Oscar his final verdict, George sends Clay to meet Mr. Henderson, the union leader at his Pittsburgh steel plant. Meanwhile, Agnes chides Ada for being too chatty during a visit with Luke Forte, Mrs. Fane arranges a match for Marian in Newport, Larry gets a new commission, and Peggy is welcomed back to 61st Street by all but one.

As the opera war heats up, an unlikely guest attends Bertha's Met fundraiser, while Agnes backs Mrs. Astor's effort to preserve the Academy's dominance. Meanwhile, Peggy offers to travel with Mr. Fortune to Alabama to cover a story about the Tuskegee Institute, Ada organizes a special luncheon for Mr. Forte, George attempts to sway Henderson, and Watson considers an offer.

After receiving discouraging news about the Met, Bertha deals with rumors that are swirling about Larry. Fearing her sister's disapproval, Ada asks Marian to cover for her as she continues to see Mr. Forte. Later, Bertha vies for position with the visiting Duke of Buckingham, and, in Tuskegee, Peggy navigates a tense dinner with Mr. Fortune and Booker T. Washington.

While Ada questions whether to move forward without her sister's support, Agnes faces the prospect of living alone. In Newport, Bertha puts the finishing touches on the event of the season as Mrs. Winterton plots her revenge. After experiencing the best of the Tuskegee Institute, Peggy and Mr. Fortune witness the dangers of the South firsthand.

As George heads to Pittsburgh to deal with the potential strike, Bertha learns that the Duke will return for the Metropolitan Opera's opening night. While the staff chip in to help Jack, Bannister tries to retrieve an incriminating letter from the Russell house. Ada and Luke return from their honeymoon and Marian receives an invitation from Dashiell.

Against the backdrop of the biggest event in New York City's history, Bertha reconsiders her loyalty to the Met. Meanwhile, an engagement celebration leaves Marian with doubts, Peggy strives to make a difference in Brooklyn, George strikes a deal with Mr. Henderson, Oscar makes an alarming discovery, and the van Rhijn household reels as Luke's health deteriorates.

While the staff question their future in the van Rhijn household, Jack receives welcome news about his patent. After scoring a victory for the local schools, Peggy considers her future at the NY Globe. Later, Marian confesses her true feelings to Dashiell – and Bertha and Mrs. Astor make their final moves in the opera war.