ABC’s ‘Castle’ season 7 spoilers: Nathan Fillion’s role in two-parter:

The two-part episode has become a rather big tradition in the 'Castle' universe, and when you remember that, you better believe that it is going to play another big role when it rolls around in the February sweeps.

So what is going to be at the center of it? We can at least confirmed that the disappearance of Richard Castle at the end of last season will be a factor in it, but there will also be something more. We told you recently about the upcoming return of Dr. Kelly Nieman, and per TV Guide, this 3XK disciple is going to be at least part of the focus in this episode.

Also, executive producer David Amann tells the site that trying to handle this case, which is tied back to a major part of Castle’s past, will force Nathan Fillion’s character to basically rethink much of his life:

“The case he’s involved with that has some emotional intensity … brushes up against his experiences that occurred while he was missing.”

In the end, all we are really hoping for when it comes to this episode is entertainment, and maybe a clue or two as to what could be coming up. In the end, we don’t want to feel like we are just going around in a gigantic circle, and do not know exactly when, why, or how we will have answers delivered.

“Castle” will return on January 12 with new episodes, one week after “The Bachelor” airs its three-hour premiere.