Author's Saving Throw: Many fans of the show questioned for years if Professor Membrane even cared about Dib. And while the movie's version of the Professor still won't be winning any parent of the year awards, it shown for certain that he loves his son — in one of the most touching moments in the history of the series, he tells Dib that he's always been proud of him and that he doesn't need to constantly prove himself. And then, despite being convinced that everything happening with Zim's Evil Plan is a hallucination he's having because he was hit on the head, Membrane doesn't hesitate to go full-on Papa Wolf to protect Dib from Zim's Mecha-Mooks.
Descended Creator: In addition to reprising the voices of Minimoose and Zim's Computer, series creator Jhonen Vasquez, also voices the new character of Clembrane (aka Clone Membrane).
The Other Darrin: The entire Italian cast was replaced, as the dub was done in Rome instead of Milan.
Most of the French cast was replaced except Martial Le Minoux as Professor Membrane, yet he uses a completely different tone for the character. Benoit Du Pac voiced the Almighty Tallest Red in the series, but in Enter the Florpus he voices GIR.
Permanent Placeholder: Jhonen had only intended to do the scratch voice for Clembrane and eventually get Justin Roiland to voice him in the special proper. By the time Roiland's schedule had cleared up, everyone had already grown accustomed to Jhonen's voice and felt it unnecessary to have it be replaced.
The film's art director is Jenny Goldberg, whom Vasquez had previously worked with on Jellyfist and the unreleased Disney Channel pilot Very Important House.
"Flibba Dibba Hoinka Smeedge" was written with Jimmy Urine; Vasquez directed the music video for "Shut Me Up" for Urine's band Mindless Self Indulgence, along with directing the music video "White" for Urine's side project, The Left Rights.
Returning Zim staff besides Vasquez include executive producer Mary Harrington, character designer Aaron Alexovich, composer Kevin Manthei, storyboard artist Christofer Graham, recording engineer Justin Brinsfield, prop designer Jeff Wong, background designer Maurice Morgan, and (in a consulting role) writer Eric Trueheart.
Reality Subtext: Referring to the massive Sequel Gap, Zim has been gone for an unspecified amount of time when the story opens. While it can't have been all that long in-universe (Dib is still only 12), it's treated by the other characters like an absence of many years, to the point where the Tallest assumed he was dead and no one really expected to see him again except for one tirelessly obsessive nerdy shut-in. Where was he this whole time? Hiding in a toilet.
Gaz: Dib, let it go. Zim's been gone a long time, and as far as you know, he might just be gone for good. I'd be willing to bet that Zim will never, ever...Oh wait, there he is.
Role Reprise: Enter the Florpus brought back a good majority of the original cast from the TV series, even those who voiced minor roles. The same can be said for the Latin American Spanish, European Spanish and Japanese dubs.
In the Brazilian Portuguese dub, Zim, Gir (Wendel Bezerra) and Dib all have their original voice actors.
In the French dub, only Martial Le Minoux reprises his role as Professor Membrane.
Trolling Creator: As per the norm with Jhonen Vasquez. In late 2016, he denied rumors that the series would be getting a movie a few days after C.H. Greenblatt claimed one was in production, pointing out that there are always rumors about Zim returning as a movie or TV series. A few months later, the first teaser for the movie was released (thought in this case, it was more likely due to non-disclosure agreements than his own tendency for sardonic jokes).
that the series would be getting a movie a few days after C.H. Greenblatt claimed one was in production, pointing out that there are always rumors about Zim returning as a movie or TV series. A few months later, the first teaser