THR Emmy Roundtable: 'Mad Men,' 'House of Cards' Showrunners on Character Surprises (Video)

Matthew Weiner explains why Duck Phillips clicked and Beau Willimon praises Corey Stoll’s “Cards” performance.

What do Duck Phillips’ large Mad Men role and Homeland’s romance between Brody and Carrie have in common? Both were unexpected surprises, say the series’ showrunners.

“We didn't even know at the beginning that Brody (Damian Lewis) and Carrie (Claire Danes) would spend time in each other's company very often,” Homeland’s Alex Gansa said during The Hollywood Reporter’s drama showrunner roundtable. “I think it was the third or fourth episode of the first season. … I remember seeing the dailies, and the word ‘chemistry’ was just flashing on the top of the screen. And I said, ‘We're gonna have to completely figure out a way to put them in each other's company in a way that we hadn't planned to before.’"

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Matthew Weiner (AMC’s Mad Men) said the Duck Phillips (Mark Moses) role was expanded after the character just clicked. He said Moses brought an authenticity to the role that won over viewers in advertising.

“Mark is a really gifted actor -- this was the last two episodes of the first season -- and I got this flood of response from people in advertising who said, ‘You finally got an account man on the show,’” Weiner said.

Beau Willimon (Netflix’s House of Cards) said the plotline involving Rep. Peter Russo (Corey Stoll) running for governor was originally meant for a different character, which hadn’t been cast.

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“Corey Stoll was doing such a great job that in the first few episodes, I thought, ‘Well, it's a monumental amount of work and a lot of painful rewrites, but let's shift that whole story to him,’” Willimon said. “Since that was a few weeks or months ahead, we could do that.”

Gansa, Weiner and Willimon were joined by fellow Emmy contenders Aaron Sorkin (HBO’s The Newsroom), D.B. Weiss (HBO’s Game of Thrones) and Kevin Williamson (Fox’s The Following).

The roundtable discussion was moderated by THR executive editor Matthew Belloni and senior editor Stacey Wilson.