Alien nation has one season of tv shows but has a great impactful story where the aliens share earth with humans.
IZombie has 5 seasons and in which the medical resident is turned into a zombie land and the detective has started the search.
Warehouse 13 has 5 seasons in which two secret agents work to protect various powerful artifacts.
The X files has 11 seasons in which Fox mulder and Dana scully investigate various weird facts and cases.
Torchwood has 4 seasons in which the detective follows an investigating sci-fi story in every format of sci-fi challenges.
Fringe has 5 seasons in which a group of FBI agents use the science process to solve mysterious cases.
Bodies have released one season but have created a great impact where the four London detectives investigate the mysterious death.