The sketch show’s 50-year history has spawned countless pop culture moments. Sketches like “Wayne’s World” led to entire movie franchises. More recently, Marcello Hernandez’s character Domingo has made meta appearances in the real world.

L ike Sally O’Malley, Molly Shannon’s spry, bouffant-sporting quinquagenarian, “Saturday Night Live” is 50 years old, limber for its age and a little too proud of itself. It isn’t hard to understand why.