Five hundred years in the future, a renegade crew aboard a small spacecraft tries to survive as they travel the unknown parts of the galaxy and evade warring factions as well as authority agents out to get them.
Most shows that get cancelled after a season or two deserve to be relegated to the ash heap. A few great shows, however, never made it past season two, leaving tons of disappointed fans in their wake. The good news is that you can binge them in a day or two.
These series cut across genres--superheroes, post-apocalyptic action, supernatural thrillers, and classic science fiction--but they should all come with a warning from the Surgeon General. Don't blame us when you mutter "one more episode" to yourself at 3 am.
What makes science fiction "hard" is a respect for logic and adherence to the known laws of physics, versus "soft" science fiction which assumes we can innovate around any limitation (often including holes in a plot). Hardness is pretty subjective (just check out the debates on Reddit), but this list includes series that are generally seen to qualify.
When the stakes are high do you call in a well functioning team of professionals--hell no, you call in a random assortment of idiosyncratic individuals who must come together as a team to complete the mission.