It’s quite simple, really:
The dudes in the studio are editing a show called The TV Show, though they’re actually broadcasting live and being watched by a guy running a noodle stand, who is in a show being broadcast on a screen on the side of a motorcycle race, which is actually a show on a giant billboard in a city under attack by a giant monster, which is really a show with miniatures and a guy in a rubber suit in a studio, which is a documentary being watched by an old couple in the mountains, which is a show being watched in an airport (which is actually a romance anime), which is being watched on a cellphone on the subway, which is being broadcast on a screen inside a video game, which is on display in a game store (which is being robbed), which is on a security tape being watched by the police, which is actually a show being broadcast in a war zone, as part of a news report, which is being watched by aliens, who are in a fictional show in a superhero cartoon, which is being watched by an artist drawing the superhero character, which is a documentary (?) being shown in a disco, which is in the background of a beer commercial, which is being broadcast at a baseball game, which is being edited by the dudes in the studio.
Got that? Because it gets a little more complicated soon afterward:
(Blatantly borrowed from Shamus Young.)