I haven't watched Lucifer yet. There's just so much good scifi and so little time!
Tonight is the season finale of The Expanse, which is on the SyFy network. It's an epic drama with a deep mythology, kind of like Battle Star Galactica.
It's based on a series of books (I've read one of them), so the story is dense and it's hard to keep track of all of the characters at first. You have to really pay attention, especially if you're bad at remembering names like I am.