Summer Glau will be making a cameo appearance in "Castle" Season 8 as Kendall Frost. Other than that, showrunner Alexi Hawley revealed what fans should expect in the 9th season. Also, ABC president Paul Lee admits that he loves the series to run for more years to come.

Summer Glau officially signs to guest star in "Castle" Season 8. According to TV Line, Glau will portray the character of Kendall Frost, a provocative private investigator from Los Angeles who competes against Castle to solve a deadly mystery case. Nathan Fillion and Summer Glau recently teamed up in an episode of fellow "Firefly" star Alan Tudyk's web series "Con Man".

Glau serves as the 3rd "Firefly" alum to co-star with Fillion in one episode of the series. The 34-year-old American actress' TV credits include "Dollhouse", "The Sarah Connor Chronicles", "Alphas", and "Arrow".

On the other hand, showrunner Alexi Hawley discussed with Deadline on what fans should expect in the 9th installment of "Castle". Hawley stated, "We wanted to wrap up a lot of the threads of different conspiracies, Beckett's mother's murder, Castle's missing time. We wanted by the end of season 8 to have gotten through all those - hopefully in a compelling and satisfying way - so season 9 can be more about the case of the week, going back to the fun of solving the case of the week and not have the luggage of past conspiracies."

Additionally, ABC president Paul Lee has admitted that he would love the Andrew Marlowe-created series to run for more years to come in their network as reported by Vine Report.

"Castle" Season 8 is set to return on February 1, 2016 at 10:00 p.m. exclusively on ABC. "Castle" is an American crime drama TV series created by Andrew W. Marlowe which is jointly produced by Beacon Pictures and ABC Studios.