As "Parks and Recreation" has progressed from season to season, one of the joys of the show has been watching the way they've built out the supporting cast, creating a world of lunatics who all live in Pawnee.

One of my favorite recurring characters on the show is Jean-Ralphio Saperstein, played by Ben Schwartz. He's not only a great foil for Tom Haverford (Aziz Ansari), he's also just a great hilarious force of nature in his own right. He's been a staple of the LA comedy scene for a while now, but Jean-Ralphio launched him to a new level of visibility, and at this point, it seems like he must work non-stop.

In recent seasons, they've started to expand Jean-Ralphio's family, first with his insane sister Mona Lisa (Jenny Slate), and more recently with his father, Dr. Saperstein (Henry Winkler). Each new thing we've learned about his family only makes him seem even weirder, and I love it. He's also a regular on Showtime's "House Of Lies," and not too long ago, he got the entire cast of that show (including Don Cheadle and Kristen Bell) to join him for a one-hour live improv special called, appropriately, "House Of Lies Live." It was great to see him play improv games with that cast, all of them out of their comfort zone.

Schwartz also has a key role in "This Is Where I Leave You," the Shawn Levy film that's been picking up amazing buzz so far, and that'll be out later this year. In the meantime, though, we've got at least one more big Jean-Ralphio appearance to look forward to this year, and it sounds like it's going to be a crazy season finale. When we spoke to Schwartz on the red carpet at the PaleyFest event, we talked about the improv special, how the mythology around Jean-Ralphio has developed, and his slow transformation into a total cartoon and how much he loves it.

"Parks and Recreation" airs Thursday nights on NBC.