Of all the sci-fi franchises, the most scientifically likely features a slow, resource-hungry, capitalism-driven expansion of humanity, leaving mundane mess in its wake, into a galaxy that features no aliens at all - Red Dwarf.
@anon_opin There's GELFs in a number of videos, despair squid & its opposite, polymorphs, whatever Camille is, and if you really want to clutch at straws there's Felix & Canine Sapiens. There are aliens, it's just Rimmer says aliens! so much it doesn't feel like it.
@FourQ @anon_opin Camille and the polymorphs are GELFs, too. They're not aliens.
@BonehouseWasps @FourQ @anon_opin And the despair squid was an evolutionary experiment by the Esperanto. Grant Naylor have said that "no aliens" was one of the in-universe rules.