On Saturday it all comes together. Runthroughs occur, Weekend Update is still being written, sets are finalized. At 7PM, the first audience is seated and the filmed dress rehearsal takes place. At this point, Lorne Michaels will make a final determination about the sketches that will be used on the live show and in which order they will occur. Typically the dress rehearsal runs long, though occasionally the sketches cut from the show will result in a show that will run short. In these instances, Lorne will plug in filmed sequences that are often repeats. This dress rehearsal is filmed just in case something goes wrong during the live show. In these instances, the dress rehearsal version of the sketch will be used in reruns.
At 11:30PM, the show is live, now coast to coast. From this point on, it is mostly smooth sailing, though there is the added stress of knowing that they’re now live in front of millions. Soon enough, it’s time to say goodnight. The cast, crew and guests will then shuffle off to a spirited after party located in the city that never sleeps. Then it is off to bed- possibly to rest up for Monday- when it probably starts up again.