Robert Duncan (also known as Rob Duncan) is a two-time Emmy-award-nominated Canadian composer of film and television music, who composed music for such TV series as Buffy the Vampire Slayer,The Unit, Lie to Me and lately Castle; and films such as Butterfly on a Wheel and Into the Blue 2: The Reef. He received an ASCAP "Top Television Series" award in 2010 for Castle and The Unit and was nominated for an Emmy for his work on season one of Castle.