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 Gene Simmons Guest Star Dominic Purcell Guest Star D.B. Sweeney Guest Star Jason George Guest Star Justice Gamble Guest Star Ryan Deal Guest Star Andrew W. Marlowe Executive Producer Rob Bowman Executive Producer Laurie Zaks Executive Producer David Amann Executive Producer Alexi Hawley Writer John Terlesky Director