I guess TV has more guts than the movie industry in terms of portraying alien invasions.
There is the currently running “Falling Skies” which begins several months after Earth has been almost totally reduced to ruins and its people decimated by a devastating alien invasion.
And a number of years ago there was a series developed from an idea originally proposed by Gene Roddenberry of the Earth being progressively taken over by the Taelons who originally appeared as friendly but were anything but. It was exec. produced by his widow, Majel Roddenberry.
“Earth: Final Conflict” ran for five seasons. Even tho produced by a Canadian company, it ran successfully on US TV.
(I think what did it in was their unfortunate penchant for killing off most major characters from one season to the next and a complete left turn switch to a different race of aliens in the fifth season.)
Other than that, it contained some really original and ingenious ideas in the first few seasons.
So, I guess TV goes further into uncharted territory than most movies dare to :)