The town of Pawnee, Indiana is famous for many things: its annual Harvest Festival , legendary jazz saxophonist Duke Silver , holding the title of fourth most obese city in America, and the miniature horse, Lil’ Sebastian (RIP). The fictional burg from NBC’s municipal comedy, Parks and Recreation, which resumes its fourth season on Thursday, has also attracted a lot of attention for its hilarious artwork, which, on many episodes, emerges from the background to steal the spotlight. Often the show has a way of turning its painted portraits into punchlines.

They’re hung with pride in the council chambers and looming lasciviously in the bedroom of ditzy morning show host, Joan Callamezzo. And each image tells a funny story. Ian Phillips is Parks and Rec‘s production designer, and he’s the one in charge of overseeing these visual tales.

Among his challenges is making images described hilariously on writers’ pages actually look funny on viewers’ TV sets.

“It’s really essential to support the visual storytelling, whether it be comedy or drama,” Phillips says. “And of course, with comedy, the driving force is to get people to really see how funny the joke can be, because it’s only on screen for a short period of time.” He adds: “The paintings are just a really fast and easy way to get a joke across. In comedy that’s really what you want–to be able to tell as many jokes as possible in as little time and have people respond to those jokes.”

The murals that adorn Pawnee’s town hall look deceptively innocent from a distance, adorned with the kind of pioneer-glorifying imagery you might find in any government building in Middle America, painted by an artist paid out of the meager civic budget. The idea behind them is that a painter came to the nascent town of Pawnee during the late-1930s and was hired to recreate these stories about its origins. In order to make them seem more period-legitimate, the paintings are created in a popular style of the time: social realism. But then you look closer, and the events depicted turn out to be horribly violent, misogynstic, and xenophobic. “If you grew up in the town of Pawnee you’d think nothing of them,” Phillips says. “And if you grew up anywhere else, you’d think they were just absolutely crazy.

“When the writers created the world of Pawnee, they came up with various funny ideas about what happened in the town–the backwardness of it throughout history,” Phillips says. “Now it’s my job to make those ideas look funny. Of course, we also don’t want to give away the joke, so the murals and artwork really have to be painted and conceptualized in such a way that they’re actually revealing the joke.”

In the second season episode, “94 Meetings,” for instance, Amy Poehler’s endlessly competent bureaucrat, Leslie Knope, tries to save a historic gazebo by explaining that 150 years ago it hosted a wedding between a white woman and a Wamapoke Indian chief. While standing in front of a mural depicting the event, Leslie describes the “beautiful” and “romantic” ceremony, and the camera remains tightly framed on a calm, peaceful wedding. Sure enough, though, Leslie eventually admits that “word got out and the reception turned into a bloodbath,” at which point we zoom out to show warring factions on either side (and also on top of) the gazebo, about to kill each other.