I always say, and I think Ben agrees with me, that the best stories are the romantic ones on a large scale. If two characters are meant to be together then nothing will keep them apart. It doesn't really matter where or how season four leaves the two characters, in our minds they were always meant for each other from the moment they met. I think that's what we've asked the audience to invest in from the very beginning.

It was very difficult for the writers to constantly come up with ways to pull them apart and then bring them together again, round and round, to find new ways to do it. We weren't underestimating the audiences intelligence, and the coin-tossing is indicative of that we were trying to find a way through that part of the story in that episode and how we could possibly separate those two characters. I suggested the coin-toss to David. It's not a perfect solution, but it goes along the lines of that huge romantic arc where the characters are placing their love and their destinies in the hands of fate. I said to Ben, David and Andrew Prowse the director, 'if they really are meant to be together, then the coin-toss is a temporary solution and it really isn't going to make a difference in the end'.

Ben and I are total romantics, total softies at heart, and we were always trying to find opportunities in every episode, in every scene. Sometimes there weren't scenes, we'd go through episodes where we'd hardly spent any time together on set at all because it was getting harder and harder to keep us in a room and not justify them not being together. But we'd always be looking for the opportunities on camera to show how much they were drawn to one another, because it's desperately romantic.