Kenya doesn't have much of an infrastructure for hosting a film of this scale. Our producer decided that for the film to really work it had to be in Kenya.

We're in a world of truncated sentences, soundbites and Twitter... [Language] is being eroded -- it's changing. Our expressiveness and our ease with some words is being diluted so that the sentence with more than one clause is a problem for us, and the word of more than two syllables is a problem for us.

And although I've been very fortunate in the film work that's come my way, I need to get back to the stage. If I'm away for a maximum of two years, I feel something's wrong.

Performance is made in the editing room, and I've come to see the truth in that - the idea that they say performances are usually made in the editing room because what you film is the raw material. I think just going through the process of saying, "Which take do we use? Why is that the take we want? I want that take can you edit again, I'm not sure that's the one, I think it's this one." And just because you go through that process, I think somehow it's made me sort of more open about the [actor's] possibilities.

Education, awareness and prevention are the key, but stigmatisation and exclusion from family is what makes people suffer most

You have to just dive over the edge. You haven't got time to mess about.

Within the process of filming, unexpected situations occur.