The Season 8 premiere of "Castle" is expected to revolve around Rick (Nathan Fillion) probing his father's disappearance and being reminded of his own that took place not long before.

TV Line also reports Castle's mom, Martha (Susan Sullivan), will still be an integral part of this season's cast.

"She's very much a part of Castle's life," co-showrunner Terence Paul Winter said. "Don't think that just because she now has her own place and is doing well on Broadway that we're not going to see her sharing her wisdom with her favorite and only son."

Previously sources revealed the new season will be highlighted by Det. Kate Beckett's (Stana Katic) life-changing decision to remain with the force and accept the promotion of captain, instead of running for the New York state senate as some had urged her to do.

"The Neighbors" alum Toks Olagundoye is also slated to come on board this season as a show regular. Playing the character of security specialist Hayley Shipton, her presence is rumored to spell huge and meaningful changes in Castle and Beckett's relationship.

Entertainment Weekly previously reported Hayley and Beckett absolutely figure to bump heads, but it'll be more about work than over the affections of Castle.

"She's a strong, powerful, beautiful, independent woman and she adds a flavor of that into the show, but is not -- in any way shape or form -- competition for Beckett," fellow co- showrunner Alexi Hawley said.

Paul Winter said, "She has a very different perspective on how she attacks cases different from Beckett, which is going to create some fun tension."

The goal insists Hawley is to add more drama and emotion to the series, while keeping many of the tenements that have made it a long-running success firmly in place.

"The important thing to say about [Rick and Kate] is that the show has always been and will always be about their love affair," he said.