For All Mankind's Krys Marshall on Danielle's journey and upcoming season 4 finale: 'Tensions are running high'

Krys Marshall is just 34 years old, but For All Mankind fans have already seen her age about as many years.

"It's been so much fun to play a character who has really grown up with us," the actress tells EW of starring as NASA astronaut Danielle Poole on the critically acclaimed Apple TV+. "I think about something like The Cosby Show: When we meet Rudy Huxtable, the actor is like 5 years old, and by later-on seasons she's in her teens. I think that the world knows what it's like to grow with a character, but never in this way, where we're watching them when we meet them they're in their 20s and now my character's in her late 50s in season 4."

As viewers brace themselves for Friday's season 4 finale, Marshall reflects on Danielle's journey over the past four years from new NASA recruit to history-making astronaut and teases what's to come in the final episode of the season as the Mars base simmers with uneasy tensions between multiple factions — not to mention between Danielle and Bob...er, Ed Baldwin (Joel Kinnaman).

ENTERTAINMENT WEEKLY: Whats the fan feedback been to this season?

KRYS MARSHALL: There's just so much great TV out there that it's really difficult to pierce through, and I feel like this season we did that in a real way, which has been just such a joy. It is totally because of the fans. In many ways — because we started shooting Season 1 in 2018, and then we premiered the end of 2019, and then the pandemic happened — it was just so much delayed gratification. Now it feels like we're finally getting to see the fruits of that labor in a real way, and the fans just love the show.

What's been the most rewarding feedback?

My Instagram DMs are flooded with girls and women who are in science and technology, women who message me who say, "I'm the only girl in my program at MIT." "I'm the only engineer in my office, and I just love your show." Women saying to me, "This is the show that I watch with my son. He and I have no shows in common, and this is the show we watch together." That makes you feel good, because it makes you feel like the thing that you make, that you love, is positively affecting people in a real way.

Each season starts after a 10-year time jump. What did you think when you first got the scripts for season 4?

At the start of season 4, we see that Danielle has experienced yet another loss — that Kuz [played by Lev Gorn] is killed in the asteroid accident. I think it is reflective of so many losses that we've seen Danielle have. In Season 1, we see her do the best she can to help Clayton [Edwin Hodge], her first husband, go through his PTSD from his time in Vietnam. We discover in Season 2 that he's now committed suicide in the break between the seasons. We see Danielle lose Danny Stevens [Casey W. Johnson] in the break between seasons 3 and 4. There's just so much loss that's happened in her life that at the start of season 4, I think Danielle's doing the best she can to amend some of that remorse and that regret.

That leads her to accept NASA's call to come out of retirement and serve as commander of the Mars base, Happy Valley...

It feels to me like her through line going through the season is, "How can I make right the things that are wrong?" When she first arrives to Happy Valley base, it's something as small as fixing the cable to make sure that folks have the bandwidth so that they can talk to their friends and family back on Earth. Then also bigger things: trying to fix the pay disparity and the disparity in treatment between the people who are working class and the people who are considered the upper class, the astronauts and engineers. I love that Danielle has always been a man of the people, and she's a fixer and she's a doer of good things. I see her throughout the season do the best she can to just try to do the right thing, and sometimes, doing the right thing ends up being the wrong thing to do.

Ed certainly isn't a fan anymore. What was it like filming that fight scene with Joel Kinnaman, and having your characters become adversarial after all they've been through?

Danielle doing the right thing by sending Ed's colleague and love interest, Svetlana [Masha Maskova], back feels like the nail in the coffin for him. He's an aging man who doesn't have a lot to look forward to. He's no longer this handsome, dashing alpha male, and this one relationship feels like the last vestige of who he used to be, and she snatches that from him. Not purposefully, but she snatches it from him.

So what can you tease of the season 4 finale? Things are coming to a head between them as Ed works with the team trying to "steal" the asteroid.

Sadly, the one connective tissue that she has, this old relationship with Ed, has begun to disintegrate — and we're watching her continue to do these two things that are juxtaposed: She's trying to do the right thing and trying to get this friendship back, trying to make this relationship work. The tensions are running high.

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