Invisible

Is it possible for the dead to remember how they came to be deceased?
Miles has been dead far longer than he can remember, unable to even recall his previous life. Being attached, or having an attachment, to a living host can have its pros and its cons, especially if the host can hear and see the dead; the afterlife isn't so lonely.
Bits and pieces of his previous life slowly start coming back to the entity, and Miles quickly learns that his death was no accident. With the help of his living host, the two, along with others, will go through hell and back to solve a mystery that has been buried for too long.
Though, it won't be just the living that they'll have to worry about along the journey.