As one of the 200,000 British members of the Church of Jesus Christ of Latter-day Saints, my heart doesn’t leap when I hear about a new documentary made about us. Such films tend not to be flattering. But here’s the puzzle: if our faith is really based on nonsense, why is it growing? Why would people like me convert? If you can bear with me, I’d like to say a bit about who we are — and what we are not.