* TheOtherDarrin: Creator/RavenSymone originally played Zenon's best friend Nebula, then Shadia Simmons played her in ''The Zequel''...then Raven again played her in ''Z3'' (though only for a cameo; Nebula's cousin Cassie [[SuspiciouslySimilarSubstitute filled her role]]).
** Protozoa, played by PhillipRhys in the first movie, gets replaced in ''Z3'' by Nathan Anderson.
** Zenon's parents get replaced in the Zequel and don't even show up in ''Z3''.
* PropRecycling: The station staff wore [=EarthForce=] uniforms from ''Series/BabylonFive''.