An omnibus edition of The Erevis Cale Trilogy (Twilight Falling, Dawn of Night and Midnight's Mask).
One, called the Sojourner, has come from the endless void. He intends to bring darkness to the Realms, whatever the cost in blood and souls.
The other will come to be known as the Shadowman, and from the darkest alleys of Sembia, he will have to take that darkness into himself, or the world will fall forever into shadow.
He was an assassin once, a thief before that, and finally a servant until his world was turned upside down. But now, the common tongue of Faerûn doesn't have a world for what Erevis Cale has become.
"Hero" will have to do.