Nathan Fillion Richard Castle Actor Stana Katic NYPD Captain Kate Beckett Actor Susan Sullivan Martha Rodgers Actor Molly C. Quinn Alexis Castle Actor Ruben Santiago-Hudson Captain Roy Montgomery Actor Tamala Jones Lanie Parish Actor Jon Huertas NYPD Detective Javier Esposito Actor Seamus Dever NYPD Detective Kevin Ryan Actor Laura Prepon Natalie Rhodes Guest Star Thomas Calabro Scott Donner Guest Star Stephen Macht Bill Wellington Guest Star Melody Thomas Scott Tonya Wellington Guest Star Randall Batinkoff Brad Williams Guest Star Andrew W. Marlowe Executive Producer Rob Bowman Executive Producer Laurie Zaks Executive Producer David Amann Executive Producer David Grae Writer Jeff Bleckner Director