Those who are experts in the fields of surveillance, privacy, and technology say that there need to be two tracks: a policy track and a technology track. The technology track is encryption. It works and if you want privacy, then you should use it.

We've already seen shifts happening in some of the big companies - Google, Apple - that now understand how vulnerable their customer data is, and that if it's vulnerable, then their business is, too, and so you see a beefing up of encryption technologies. At the same time, no programs have been dismantled at the governmental level, despite international pressure.

We don't stand here alone, it's possible through the great organisations that support us. The disclosures that Edward Snowden revealed aren't only a threat to privacy but to democracy, when the most important decisions made affect all of us. Thank you to Edward Snowden. I share this with Glenn Greenwald and other journalists who are exposing truth.

I think one of the most shocking things is how little our elected officials knew about what the NSA was doing. Congress is learning from the reporting and that's staggering. Snowden and [former NSA employee] William Binney, who's also in the film as a whistleblower from a different generation, are technical people who understand the dangers.

In all my work, I'm interested in understanding big issues through the lives of individuals.

One of the most frightening things, I think, is the capacity for retroactive searching, so you can go back in time and trace who someone is in contact with and where they've been.

Those who are experts in the fields of surveillance, privacy, and technology say that there need to be two tracks: a policy track and a technology track. The technology track is encryption. It works and if you want privacy, then you should use it.