Chris Pratt and Amy Poehler wait on set for "Parks and Recreation," taping in front of the U.S. Capitol. (NBC)

It’s a typical Friday afternoon in July at the Smithsonian’s National Museum of American History. Tourists in khaki shorts haul their digital camera gear from exhibit to exhibit. Security guards keep mindful, silent watch. And Chris Pratt and Aubrey Plaza, two of the stars of NBC’s “Parks and Recreation,” passionately make out on the floor a few feet from the famous Southern Railway 1401 steam locomotive.

Hey, they were just doing their jobs. And their jobs during a two-day shoot in D.C. that bounced to five downtown locations — including the Lincoln Memorial, the White House, the Capitol, the Hay-Adams Hotel and various sections of the American History museum — sometimes involved making monumental idiots of themselves while surrounded by monuments.

“I don’t think we were supposed to” do that, Pratt said earlier in the day, after a scene in which his character — the affably empty-headed Andy Dwyer — lay belly-down on the steps of the Lincoln Memorial and picked up discarded gum. “But we did.”

Pratt, Plaza and their fellow “Parks and Rec” stars Amy Poehler and Adam Scott were in town to shoot scenes for the Emmy-nominated series’s fifth season, specifically an episode that brings Dwyer and Leslie Knope (Poehler) from Indiana to Washington to visit Ben Wyatt (Scott), Knope’s congressional campaign strategist boyfriend, and April (Plaza), who piggybacks on his temporary Washington assignment by becoming his assistant.

According to executive producer Michael Schur, the episode is an opportunity for Knope, now a city council member in fictional Pawnee, Ind., to consider whether she wants to go to “the next level of American politics.” It’s also an opportunity for perhaps the biggest political nerd on prime-time television to geek out over the Washington Monument and the first ladies’ dresses at the Smithsonian. While Scott’s and Plaza’s characters will remain in Washington for five episodes, Schur says there are no plans for production to return.

During Friday’s shoot, onlookers kept their distance from the cast, largely opting to stay out of the way and shoot cellphone photos from afar. But Poehler says some “Parks and Rec” fans definitely made themselves known.

“We saw a guy yesterday that, independently, was wearing a Mouse Rat T-shirt,” she says, referring to Dwyer’s band on the show. “Like, on his own.”