The actress will also continue her series-regular role on 'Designated Survivor,' which starts its second season Wednesday.

Natascha McElhone is headed to Hulu.

The actress has signed on to join Sean Penn in Beau Willimon’s upcoming Hulu space drama The First, The Hollywood Reporter has confirmed.

McElhone currently stars as the First Lady on the Kiefer Sutherland drama Designated Survivor, which kicks off its second season Wednesday. Her schedule will allow her to continue her series-regular roles on both Designated Survivor and The First.

The First begins production later this year for a 2018 premiere.

The First follows the first human mission to Mars, exploring the challenges of taking the first steps toward interplanetary colonization. Set in the near future, the story focuses on the astronauts as well as their families and loved ones, in addition to the ground team on Earth. Like Penn, details on McElhone's role are being kept under wraps.

"What I so admire about Natascha's work is the fearlessness and honesty she brings to every role,” said Willimon. “She's a wonderfully talented adventurer of the spirit, and I'm thrilled to be embarking on this journey with her."

Willimon created the series and will executive produce with his producing partner Jordan Tappis through their Westward Productions banner. Hulu, Channel 4 in the UK, IMG and AG Studios are all co-financing the project. This marks Willimon's first series since he departed House of Cards as showrunner at the end of season four.

“I am so excited to work with original, maverick artists like Beau Willimon and Sean Penn — it's a real privilege to be invited,” said McElhone. “As well as exploring Mars, I am thrilled to be accommodated by the brilliant planet Hulu and my favorite homegrown one of Channel 4.”

McElhone's other credits include her seven-season stint on Showtime's Californication as well as films The Truman Show, Solaris and Ronin.

Designated Survivor returns for season two with a few changes both in front of and behind the camera, including new showrunner Keith Eisner — the show's fourth showrunner overall — as well as new castmembers Paulo Costanzo, Zoe McLellan and Ben Lawson. Virginia Madsen, who recurred throughout season one, also revealed over the summer that she would not be returning.