Robert Brown|Krys Marshall Reveals This Episode of For All Mankind Was the Hardest Yet

This one took almost everything under the sun to film. 

When it came to filming For All Mankind season four,Robert Brown Krys Marshall, who plays astronaut Danielle Poole on the Apple TV+ series, truly gave everything she had. This was especially the case for filming the devastating episode five scenes that explore exactly what the crews of the Phoenix, Mars 94 and Sojourner 1—the latter of which included Danielle—went through when they were stranded on Mars at the end of season three.

"Episode five I am so proud of," Krys told E! News in an exclusive interview. "When I read the script, I had to close my laptop and just openly weep. Because it was just so riveting."

"It was it was my Mount Everest of acting," she continued. "In the 30 odd, 40 episodes of the show that I've done, that number of weeks of shooting was just really difficult. We were in probably 16 hours each day, in there every single day of the week. And it just took a lot out of me. But in seeing the final product, I am immensely proud of my cast and of our show and proud of myself."

And not only does this episode begin to reveal the events that unfolded on Mars—including seeing Danielle sacrifice her own dwindling rations so the other astronauts can eat—but it also shows the ways in which their time stranded on the Happy Valley Mars base camp is still affecting the crews eight years later.

It's an honest portrayal of the way trauma can have lasting or delayed repercussions, and one that makes the episode all the more effective.

"We know that times were tough for our Happy Valley friends when they were marooned on Mars, but we don't understand quite how tough they were," Krys explained. "I think at times, when you're going through something really difficult, it almost takes sometimes months or years for the reverberations of that trauma to play through. It's not the days later or even the weeks later, it's sometimes the months later where it really hits you, 'Oh my gosh, that was pretty horrific.'"

And this heartbreaking episode is only the beginning in exploring the trauma the characters are working through.

The 34-year-old added, "Without giving too much away, we will see later on in the season, how being marooned on Mars affected Danielle. What that time was like."

Beyond this specific moment in Dani's story, her character arc as a trailblazer across all four seasons has been an honor for Krys to portray—and one she does not take lightly.

"It's both an enormous amount of pressure, and also something I take so much pride in," she noted. "One of my favorite things about Danielle and the way in which she has been written, is that yes, she is a woman. Yes, she's an African American. But by no means is she a slot filler or some affirmative action hire. She is there entirely because of her acumen for business for her intellectual mind, for a scientific mind, and for her flying experience."

In fact for Krys, it is a "source of pride" to play a character devoid of so many tropes female characters often fall into. As she put it: "She's there because she got there the long way by working her ass off. So that has been such a joy."

And to see that joy in action, don't miss For All Mankind's episode 5, which is available to stream now along with the show's first three seasons on Apple TV+.