This was such a boring read, it is kind of ridiculous.
The Darkest Night is supposed to be a PNR book a-la-J.R. Ward - while there are many similarities, Showalter ultimately does not deliver. The book is filled with tortured fallen angels, forced to host a demon within them. But apart from being tortured, they are utterly indistinguishable. This is the case for the entire book - we are introduced to so many characters and none of them seemed to have a personality!
The heroine, Ashlyn, was a complete bore - and what little character she did have made me roll my eyes. She's psychic, and Maddox is the only one who can calm the voices. She's a virgin, but addicted to pornography. Ooh. Aaah - BLEH.
The cover sure is lovely, though, and the writing itself was pretty ok. It could well be that the books miraculously get better later on. But I'm afraid I won't be sticking around to find out.
Bottom line? A book filled with PNR tropes and zero emotional pulls. Skip it.