The UK's cybersecurity and intelligence agency GCHQ is on a mission: to shift its public image away from secretive agency

From the outside, the headquarters of GCHQ — the UK’s cybersecurity and intelligence agency — looks exactly how you’d expect: barbed wire fences and security checkpoints.

But once you’re inside, things start to feel a lot less James Bond and more like a giant shopping centre.

There’s a Greggs bakery (the baristas have security clearances) and, next to it,…