| Nathan Fillion | Richard Castle |
| Stana Katic | Kate Beckett |
| Susan Sullivan | Martha Rodgers |
| Jon Huertas | Javier Esposito |
| Seamus Dever | Kevin Ryan |
| Tamala Jones | Lanie Parish
(credit only) |
| Molly C. Quinn | Alexis Castle
(credit only) |
| Toks Olagundoye | Hayley Shipton
(credit only) |
| Jewel Staite | Erin Cherloff |
| Marco Rodríguez | Jorge 'El Oso' Zamacona
(as Marco Rodriguez) |
| Juliana Dever | Jenny Ryan |
| Marco Zunino | Hector Zamacona |
| Gabriel Salvador | Alejandro Guzman |
| Claudio Pinto | Johnny Toro |
| Michelle Alegria | News Anchor |
| Ken Colquitt | DEA Agent Richmond |
| Jonny Cruz | Zane Cannon |
| Eileen Fogarty | Élodie |
| Emily Goss | Naomi Fox |
| Andrew Elvis Miller | Jake Cuneo |
| L.T. Tolliver | LT
(as LT Tolliver) |
| Madelyn Witkin | Sara Grace Ryan |
| Roman Mitichyan | Rayas Thug
(uncredited) |