The British actress was exhausted after arriving at an airport and broke down, but an inconsiderate admirer tried to get her to take a snap with them.
As a result, she's ruled out taking selfies with fans in future - but is happy to greet them and sign autographs.
"I was walking through an airport and I started having a panic attack brought on by complete exhaustion," she tells British musician Jessie Ware on her "Table Manners" podcast. "I'm crying and this guy's like, 'Can I get a selfie?' And I was like, 'I can't breathe, I'm really sorry... ' It was after a few moments like that where I was like, 'I don't know how to do this'."
Explaining her policy, and that she's still approachable most of the time, Emilia adds: "I will sign something. When you do that you have to have an interaction with that person, as opposed to someone just going, 'Give us a selfie, goodbye'. It turns into, 'Right, what's your name? Who am I making it out to?'
"Then you have a chat and you're actually having a human-to-human thing, as opposed to it being this thing that probably isn't nice for them or you."