Bill Hader Explains The Origin Of 'Stefon' On Fallon (VIDEO)

On Friday night's "Late Night," Jimmy Fallon had fellow "Saturday Night Live" cast member Bill Hader on to talk about the latest season. At the start of this clip, the two trade Robert De Niro impressions since the Oscar winner will be hosting "SNL" for the first time this month. It's hard to tell whose was better, but Fallon also dished that Tina Fey had one of the worst De Niro impressions of all the "SNL" cast members.

Hader and Fallon then launched into a discussion of one of our favorite characters as of late, Stefon, the shy, club-going City Correspondent on Weekend Update. Watch Hader explain how Stefon came to be after an email was sent to "SNL" writer John Mulaney about a club filled with outrageous things like "Ferkels" (fat Erkels) and Hader became fascinated with an eccentric barista in Chelsea.