1: Movies (moo-vies); The third in a series of movies each linked by plot elements to the next, usually referred to as the "shittiest" sequel.
2: Cartoons (kar-toonz); The third successive episode of a season of a given cartoon is referred to as Episode 3, season X. Typically, this will be the last good episode in a cartoon, except in the case of the Simpsons, in which case it will be the first of many. (Note: After Season 3, the Simpsons no longer made any good episodes at all.)
The third episode in the Battle Kid Game Grumps series, in which one of the hosts, Arin Hanson, has various mental breakdowns due to being unable to beat a boss. In the end he quits the game by mistake. This phrase can be used when talking about a horrible experience.