Under the Gaze (INCOMPLETE)

Chris O'Connor, a retired detective, had sworn to never touch any of the crime business ever since he helplessly let a serial killer slip away without a single trace. He tried to refresh his life in different ways, trying to forget that he did such a failure; But none of it worked. The image haunted him night and day that he'd kill everyone he sees; blaming him for his actions of letting him slip away.
One day, when he came home, just on the day after 9 years of the killer's disappearance, his entire family was long gone.
There wasn't a single trace - No blood, no signs of savage, nothing at all could reach them.
Could this be the work of the killer, or is this all a coincidence;
Will Chris finally set himself free from the embrace of his failures, will he finally get the killer?
Furthrmore:
Who is the killer?