William Thomas Hader Jr. is an American actor, comedian, writer, producer, and director. Hader gained widespread attention for his eight-year stint as a cast member on the long-running NBC sketch comedy series Saturday Night Live from 2005 to 2013, for which he received four Primetime Emmy Award nominations and a Peabody Award. He became known for his impressions and especially for his work on the Weekend Update segments, where he played Stefon Meyers, a flamboyant New York City nightclub tour guide.

Saturday Night Live (SNL) is an American late-night live sketch comedy variety show created by Lorne Michaels and developed by Michaels and Dick Ebersol that airs on NBC and streams on Peacock. Michaels currently serves as the program's showrunner. The show's premiere was hosted by George Carlin on NBC on October 11, 1975, under the original title NBC's Saturday Night. The show's comedy sketches, which often parody contemporary American culture and politics, are performed by a large and varying cast of repertory and newer cast members. Each episode is hosted by a celebrity guest, who usually delivers the opening monologue and performs in sketches with the cast, with featured performances by a musical guest. An episode normally begins with a cold open sketch that was usually based on political events and ends with someone breaking character and proclaiming, "Live from New York, it's Saturday Night!", properly beginning the show.