If I remember correctly, Roger Collins, like Barnabas, was supposed to be a short-term character, but was kept on instead. And I can sure see why. Louis Edmonds is so much fun to watch!
I caught myself thinking, as Sam wrangled with Roger, "Why doesn't he just explain to Burke?" And then - oh, yeah! - I remembered why. I'm not made for a life of deception, and neither is Sam.
Was any effort made to cast Ned Calder?