CASTLE & BECKETT HAVE THEIR MURDER CASE TAKEN OVER BY A FEDERAL AGENT (ADRIAN PASDAR) IN A TWO-PART STORYLINE, ON ABC'S "CASTLE"

"Setup" (Part 1) -- Castle and Beckett investigate the apparent robbery-homicide of a New York cab driver, only to discover that the victim was involved in a mysterious conspiracy with unimaginable consequences. As the stakes continue to rise, hard-charging federal agent Mark Fallon (guest star Adrian Pasdar) takes over the investigation. Together, Fallon, Beckett and Castle must race to unmask the truth about the victim before it's too late, on "Castle," MONDAY, FEBRUARY 21 (10:01-11:00 p.m. ET) on the ABC Television Network.

"Castle" stars Nathan Fillion as Richard Castle, Stana Katic as NYPD Detective Kate Beckett, Susan Sullivan as Martha Rodgers, Molly Quinn as Alexis Castle, Ruben Santiago-Hudson as NYPD Captain Roy Montgomery, Tamala Jones as Medical Examiner Lanie Parish, Jon Huertas as NYPD Detective Javier Esposito and Seamus Dever as NYPD Detective Kevin Ryan.

Guest Cast: Adrian Pasdar as Agent Mark Fallon, Victor Webster as Josh Davidson, Bahar Soomekh as Nazihah Alhabi, Lochlyn Munro as Kevin McCann, Alon Aboutboul as Fariq Yusef.

"Setup" was written by David Amann and directed by Rob Bowman.

"Castle" is broadcast in 720 Progressive (720P), ABC's selected HDTV format, with 5.1 channel surround sound. A TV parental guideline will be assigned closer to airdate.

For more information on "Castle," visit ABC.com. Viewers can also follow the show via http://facebook.com/Castle and Twitter: Castle_ABC