Iain de Caestecker described his character in the shows as, "young and a bit arrogant." He plays Duncan Knock, special advisor to Peter Laurence. But as we see from the first episode, he's not always got Peter's best interests in mind as he tries to make his way up the political ladder, too.
The actor has had a number of different roles in TV, including Coronation Street and Marvel's Agents of S.H.I.E.L.D.