Washington (CNN) Former secretaries of state Hillary Clinton, Colin Powell and Madeleine Albright offered their fictional successor Elizabeth McCord some advice on the rise of white nationalism in America Sunday on CBS's "Madam Secretary."

The three secretaries of state popped up in the season premiere to counsel McCord, played by Tea Leoni, after a white nationalist group commits a terrorist attack in Washington, DC, and spoke about the importance of cultural diversity in America.

"I think what we're all saying is talk about what unites us," Clinton says to Leoni's character in the episode. "Even in this moment of peril, remind Americans of our nation's original motto, something that I think about a lot and which seems more important today than ever: E Pluribus Unum."

Albright, who made her first cameo on "Madam Secretary" in 2015, said in video provided exclusively to CNN that she enjoys how the show engages with real news issues.

"I think what's so great about the show is that it actually discusses events that could be taking place," Albright said. "And that there are real people that have to make decisions that have husbands and children."

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