The 2018 Eurovision Song Contest is being held tonight in Lisbon, Portugal, and the ninth person to perform their song was the UK's entrant, SuRie, singing her song "Storm".
Halfway through her performance, an audience member ran onstage and grabbed SuRie's microphone out of her hand.
Security guards immediately jumped onstage to intercept the man, and the camera cut to British supporters in the audience.
And SuRie was left onstage without a microphone for 15 seconds.
She quickly got her microphone back, and totally nailed the rest of her performance.
When the man grabbed the microphone, he shouted: "Nazis of the UK media, we want freedom".
The man has been identified as Dr A.C., a self-proclaimed activist who pulled the same stunt earlier this year at the National Television Awards and during the finale of The Voice last year.
The rules of the Eurovision Song Contest meant that, because her performance was interrupted, SuRie would be allowed to perform again later in the show if she chose to.
However, SuRie decided against performing for a second time.
Here's a video of the moment in full:
A representative for the Eurovision Song Contest has been contacted for comment.