This contains almost no dialogue, with the exception of the cold open and the final few seconds.
Inspired by the film "Lost in translation"
Though this takes place underwater and its inhabitants are sea creatures, none of them are shown swimming.
Bojack is warned that a thumbs-up is an insulting gesture underwater (which leads to the failure of his attempt to hitchhike). This is true in several parts of the real world.
Wallace Shawn shows up at the underwater premiere. The real-life actor has no lines.