Josh Stamberg is set to play an "important" role on Castle, according to creator Andrew Marlowe.

The former Drop Dead Diva star will come on board the two-part February Sweeps episode - which also features Jennifer Beals - as an intelligence officer.

Beals will appear on the special installment as a CIA agent who teams up with Castle and Beckett when another agent goes rogue.

Look for Castle to air its first episode of 2012 on Monday, as Ryan and Jenny walk down the aisle. Return to TV Fanatic later in the week for an interview with star Seamus Dever in which he discusses this union.