Elle Fanning and Nicholas Hoult on Gillian Anderson's arrival in The Great season 2: 'She's a tornado'

When the offer to join The Great season 2 came her way, Gillian Anderson knew two things.

One, the scripts reminded her of Monty Python-esque humor, and she desperately wanted to join the fun. And two? "I also wanted to work with Elle [Fanning]," the two-time Emmy winner tells EW for our latest digital cover story. "I'm a big fan of her and I think she is phenomenal. I really wanted to get to work with her, and she didn't disappoint."

Anderson joins the upcoming season of the irreverent Hulu series as Joanna Elisabeth of Holstein-Gottorp, the mother of Catherine the Great (played by Fanning), who is appalled when she hears word of her daughter's coup. As the maestro of arranging advantageous marriages for her daughters, Catherine taking the throne from Peter (Nicholas Hoult) has made things more complicated for Joanna. She travels to Russia to see if she can dissuade Catherine from her plans.

Anderson's admiration for her onscreen daughter goes both ways. Fanning says when Anderson first came to set, everyone was on their best behavior out of reverence for the star. "Normally we're just wild and crazy, but we were like, 'Oh my god, Gillian Anderson. Gillian, she's coming, she's coming, she's coming.' It was a lot like mother's coming," Fanning admits.

Joke was on them though, because it turns out Anderson is quite the "goofball" herself. Case in point: Fanning says that when showrunner Tony McNamara first told Anderson about her character's most outrageous scene, the actress didn't even bat an eye. "She was like, 'Okay, I'm in.' Which tells you so much about her, because it's so insane. But she's down for anything. She'll try anything," Fanning says, adding, "I'm happy she's my 'mum.'"

Fanning's character, however, might have slightly different feelings on the matter. "[Her mom] is like a tornado of coming in and you get to see Catherine [in such a] different way. She's reverting back to her childlike ways with her mom and trying to please her," Fanning explains.

Catherine isn't the only character who gets to share the screen with Anderson's Joanna. Some of her most delicious moments come from her interactions with Hoult's Peter. "The way she can come in and command such power over people is incredible — both over Catherine and Peter," Hoult explains. "And there's such a strange dynamic setup in the beginning of that, a really fun one for me to play with her, where she has complete control and power over him. He honestly is just fighting to be away from her a majority of the time because he can't handle being around her."

Joanna only comes in for two episodes this season, but her arrival shakes up the entire court, which Hoult says was "brilliant" to watch unfold. "The different strategies that she employs in each scene with each character, it was fun to see how that character would behave so drastically differently depending on who they were in the scene with," he says.

Hoult continues, "It's putting the cat amongst the pigeons a little bit because everyone at court has got their rhythms and patterns with different characters, and then suddenly you put Gillian in the middle of it and it just completely throws everyone up in the air. Everyone's scrambling to figure out where she stands, how she affects them, and what they can do to try and benefit, or at least stop them from being affected negatively by it."

It was all a bit unusual for Anderson — who counts starring roles on Sex Education and The Crown among her recent credits — to come in in the middle of the action among an already established cast. "It's an interesting thing. I don't feel like I've done that very much," she says. "It's certainly a different dynamic coming in as a guest star than something that you start from the beginning, and grow together with, and know the crew inside out. But everybody was so lovely, and delightful, and welcoming, and made it really, really easy to just slip in. They made it feel kind of effortless, in a way."

Ultimately, she says she's grateful for the experience and excited for fans to see it. She says, "It was such fun with everybody, and I really loved working with them, and appreciated how much they gave, and how great they all are." Pun intended.

All 10 episodes of The Great season 2 drop on Hulu this Friday.

Related content:

• From Russia With Love: The Great stars Elle Fanning and Nicholas Hoult on their challenging and surprising second season
• The Great stars Elle Fanning and Nicholas Hoult reign over EW's digital cover shoot
• The Great season 2 trailer features more scheming, innuendo, and talk of beheadings