House of Cards Season 4 left us on a pretty grim note, and our first new additions for Season 5 aren’t any less intimidating. Not only has the icy Patricia Clarkson joined in an important new role, but also a familiar Royal Pains star.

The Hollywood Reporter made the first House of Cards Season 5 casting announcement, revealing that both Six Feet Under and Parks and Recreation star Clarkson and actor Campbell Scott have booked “major” mystery roles in the 2017 season, said to be “featured heavily.” Predictably, Netflix declined to identify the nature of their characters, at least until we get closer to next year’s premiere.

Elsewhere of Season 5, House of Cards senior writers Frank Pugliese and Melissa James Gibson will jointly move into the showrunner position, having joined the breakout Netflix original drama back in its third season. Original creator and showrunner Beau Wilimon exited alongside the Season 5 renewal in January, having been with the series from the beginning.

It’s likely Season 4 stars like Neve Campbell and Suicide Squad star Joel Kinnaman will also return for Season 5, but what other terrors might House of Cards have in store next year?

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