After her father dies in 1882, Brook is forced to move from rural Pennsylvania to New York City to live with her wealthy aunts, Agnes van Rhijn (Baranski) and Ada Brook (Nixon), who are part of an aging class of high society reckoning with the influx of ambitious and self-made newcomers, including railroad tycoon George Russell (Morgan Spector) and his ambitious wife, Berth (Coon).
Joining Brook is Peggy Scott (Denée Benton), an aspiring writer who finds herself employed by the aunts, as the two get caught up in a social, class and economic war between old money and new money and question whether they should follow long-standing traditions or forage their own paths.
And along the way, Brook and Scott develop their own friendship, even though they must navigate racial and age barriers of the time. “We felt it was very important that Marian and Peggy don’t become fast friends and that Marian is somehow free of the biases of her time. Like, she wouldn’t have the same assumptions and stereotypical ideas about Black women her age,” Jacobson tells ET’s Rachel Smith of building the characters’ dynamic with Benton.
For Jacobson, whose mother just so happens to be Meryl Streep, the role marks her series debut after first appearing in the 2019 TV movie, Gone Hollywood, starring Nikolaj Coster-Waldau and Jonathan Pryce. Prior to making her debut, the youngest of Streep’s four children studied psychology at Vassar College before attending British American Drama Academy in Oxford and later earning a Master of Fine Arts in Acting from the Yale School of Drama.
It’s actually while spending a semester abroad in London (“I was studying psychology at University College London,” she says), that she first discovered and became a fan of Downton Abbey. “I think it was every Sunday night [when] Downton would come on and I would just geek out over it,” Jacobson shares. “I just loved it.”
Now, just over a decade after that series first premiered in the U.S. in 2011, Jacobson is living out a dream of her own, feeling like “a princess at times,” she says, gushing over the lavish costumes that help bring each of the characters to life onscreen.
“The costumes were such an integral part of how I got into the character and into the world basically of that period,” she says. “I had a love-hate relationship with them at times. Some of the dresses were like my childhood dream come true. But that was also annoying and I think as a modern woman now, I found it frustrating and constricting.”
But in the end it helped with her performance. “It fed Marian and her engine to want to break free of boundaries,” Jacobson says, giving credit to costume designer Kasia Walicka-Maimone. “She is a genius. It was exciting to see how Marian’s costumes sort of mirror her progression throughout the season.”
Not only was Jacobson starring in a Fellowes creation, but she was doing so alongside so many esteemed TV and theater icons. And for the rising star, it was an opportunity to make her mark with the ingenue character but also learn from those around her. “It was a learning curve for me,” she says of finding her footing with Baranski and Nixon, in particular. “They are amazing and they were so patient and gracious with me. They just have wonderful energy, both of them. And they’re just so different in their own ways.”
Lucky for Jacobson, Baranski is no stranger to the Streep family. “They’re a bit of a dynasty at this point,” Baranski quips when it comes to Streep and her daughters, including Grace and Mamie Gummer. In addition to sharing the screen with Streep in films like the Mamma Mia franchise and Into the Woods, Baranski has also acted alongside Mamie Gummer, who has guest-starred several times on The Good Wife and its spinoff, The Good Fight.
In fact, in “the span of one week,” a “delighted” Baranski recently went from working with Jacobson on The Gilded Age to spending time in the courtroom with Mamie Gummer’s reprisal of Nancy Crozier on The Good Fight.
And when it comes to working with Jacobson specifically, Baranski says that any nerves her co-star had about being on set worked for the character. “It was really sweet with Louisa because her character [is new to] this world. She’s very insecure but she's got this tough hand. And on the other hand, she's nice. But it was very much what Louisa was living through as this young actress who gets this juicy role.”
Baranski adds, “I saw her start out being able to use all her insecurities and all that being very real and it was a joy to watch her as an actress as well as a character. She’s marvelous and I think Meryl will be very proud.”
The Gilded Age premieres Monday, Jan. 24 at 9 p.m. ET/PT on HBO and HBO Max.