"Castle" has cast "Mob Doctor" alum James Carpinello for a Season 6 guest role, HuffPost TV has learned exclusively.


Carpinello will appear in episode 607, “Like Father, Like Daughter,” playing Frank Henson, a man incarcerated on death row for a murder he claims he did not commit. Castle (Nathan Fillion) and Beckett (Stana Katic) -- and Alexis (Molly Quinn) --– soon get involved in the case.


Carpinello's other notable credits include "Gangster Squad," "The Good Wife," "So noTORIous" and Broadway stints in "Saturday Night Fever" and "Rock of Ages." The actor also shares a Joss Whedon connection with Fillion -- Carpinello is married to Amy Acker, who co-starred with Fillion in Whedon's "Much Ado About Nothing" (and in three episodes of Fillion's shortlived Fox series "Drive," created by "Angel" executive producer Tim Minear).


Also set to make appearances in "Castle" Season 6 are Lisa Edelstein, who will play a tough federal investigator with ties to Beckett; Glenn Morshower, who has been cast as a secretive general; Warren Christie, who plays a reporter with a penchant for uncovering stories that are detrimental to national security; Joshua Bitton, who will play a new detective at the 12th Precinct who is eager to prove himself; Antonio Sabato Jr., who is cast as Ramon Russo, an actor best known for his role on the fictional "Saved By The Bell"-esque '90s sitcom "2 Cool For School", and Yancey Arias, who will appear in the first two episodes of Season 6 as Carl Villante, the head of an elite investigative unit who butts heads with both Beckett (Stana Katic) and Castle (Nathan Fillion).


"Castle" Season 6 premieres Monday, Sept. 23 at 10 p.m. ET on ABC.



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  • Castle Season 5


    Stana Katic as NYPD Detective Kate Beckett.




  • Castle Season 5


    Seamus Dever as NYPD Detective Kevin Ryan.




  • Castle Season 5


    Penny Johnson Jerald as NYPD Captain Victoria Gates.




  • Castle Season 5


    Jon Huertas as NYPD Detective Javier Esposito.




  • Castle Season 5


    Molly Quinn as Alexis Castle.




  • Castle Season 5


    Nathan Fillion as Richard Castle.




  • Castle Season 5


    Susan Sullivan as Martha Rodgers.




  • Castle Season 5


    Tamala Jones as Medical Examiner Lanie Parish.




  • Castle Season 5


    "Castle" stars Jon Huertas as NYPD Detective Javier Esposito, Tamala Jones as Medical Examiner Lanie Parish, Seamus Dever as NYPD Detective Kevin Ryan, Molly Quinn as Alexis Castle, Susan Sullivan as Martha Rodgers, Nathan Fillion as Richard Castle, Stana Katic as NYPD Detective Kate Beckett and Penny Johnson Jerald as NYPD Captain Victoria Gates.