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 Corey Saunders Derek Brookner Guest Star Mary Page Keller Rebecca Dalton Guest Star Philip Anthony-Rodriguez Michael Grant Guest Star Blake Gibbons Billy Grimm Guest Star Sam Doumit Mandy Carson Guest Star Samantha Quan Kathleen Park Guest Star Christina Vidal Jamie Ruiz Guest Star Gideon Emery Lloyd Saunders Guest Star Andrew W. Marlowe Executive Producer Rob Bowman Executive Producer Laurie Zaks Executive Producer David Amann Executive Producer Elizabeth Davis Writer Felix Alcala Director