'Sightseers' started off as a character comedy double act.

I think in most couples or partnerships, there's a constant struggle for power and dominance.

The film [Sightseers] is really the story of the journey of a relationship, so the killings are almost a metaphor for the trials they go through. We wanted people to identify with the experience of going on holiday and having a quarrel with your wife, boyfriend, whatever. We knew if we didn't crack that it would not be watchable as a film.

Manchester has a certain reputation of being cool.

Both of us have forged our careers in London, but a lot of my comedy influences come from my family and my childhood.

I think what's difficult is proving to people that a script actually does work and sometimes the laughter might not be on the page, it might be between the lines.

We actually did go on a camping trip together as part of the research, in a caravan, for a week. I guess we picked who annoyed us most from genuine experience. We did a lot of research on camping and what annoys people. It's quite often children playing ball games. It's a huge debate in the caravan world whether children should be allowed to play ball games or not.