The Gilded Age

In Arizona, George faces opposition while unfurling his ambitious plan to build a train route connecting New York, Chicago, and Los Angeles. Back in New York, Bertha prepares for the Duke's imminent arrival, Peggy falls ill after an unseasonable snowstorm, and Ada hosts a gathering to support the temperance movement – to Agnes' chagrin.

Concerned about Peggy's worsening condition, Agnes and Ada welcome her parents and their physician, Dr. Kirkland, to 61st Street. Meanwhile, Oscar gets a professional favor from an old friend, Bertha makes her case for the Duke to a skeptical George, and Gladys suffers a heart-breaking disappointment.

As negotiations with the Duke start to disintegrate, George confronts Bertha about her vision for Gladys – and its inadvertent impact on his business. Meanwhile, the Scotts meet the Kirklands in Newport, Ada encourages the staff to sign a temperance pledge, Agnes laments her slow exclusion from society, and Larry invites Jack to a meeting with a potential investor.

With the wedding between Gladys and the Duke imminent, Bertha must deal with unwanted rumors in the press, the sudden arrival of her sister Monica, and an unwilling bride. After giving a talk in Newport, Peggy and her mother encounter the aloof Mrs. Kirkland. Meanwhile, a grieving Ada attempts a new way to communicate with Luke, and Borden learns more about Mrs. Bruce's past.

In England, Gladys has trouble adjusting to Lady Sarah's controlling authority over the household. After a string of personal and professional wins, Larry invites Jack out to celebrate – and spots a familiar face. While at an event with Dr. Kirkland, Peggy gets an opportunity from an old colleague. Later, drama ensues at Mrs. Fish's Newport luncheon.

While Bertha encourages Gladys to stand up for herself and her new husband, George faces an upward battle to secure the rail line that runs through Chicago. Larry gains intel that leads Oscar to have a long-awaited confrontation – but raises doubts for Marian. Later, Peggy confides in Dr. Kirkland about her past, and Ada has a candid talk with Jack about his future.

Amid the release of a salacious book, Mrs. Astor discusses the future of her Newport ball with Bertha. After returning from Arizona, Larry shares a promising discovery with George, only to receive troubling news in return. Meanwhile, Mrs. Kirkland receives concerning information about Peggy, and the Russell household uncovers the source of recent leaks to the press.

Despite objections from Mrs. Astor, Bertha finalizes the guest list for the ball – and finally faces the fallout of her actions. Meanwhile, Dr. Kirkland makes a decision about his future with Peggy, Oscar reconnects with a previous ally, and Marian struggles to move forward.