The US has denied entry to a 21-year-old Syrian behind an Oscar nominated documentary because of problems with his documents.
Khaled Khatib did most of the filming for a British movie called The White Helmets.
It's a 40-minute Netflix documentary about volunteers who risk their lives to rescue civilians.
It's widely thought to be one of Britain's best chances for an Oscar in the short documentary category.
Khaled Khatib is part of the White Helmets group and he helped film the organisation which operates in parts of rebel controlled Syria.
The country is in the midst of a bloody war which has killed an estimated 500,000 and a further 11 million have either fled their homes or the country.
Khaled Khatib was supposed to be flying in to the US from Turkey for the 89th Academy Awards.
But he was stopped by Turkish officials in Istanbul earlier this week, and they referred his case to the US Embassy in Ankara.
Sources in Ankara told the BBC the filmmaker had a problem with his passport.
And the US Department for Homeland Security stated: "A valid travel document is required for travel to the United States."
Khatib tweeted on Saturday: "After 3 days at airport, not allowed to travel to #oscars2017 - had US visa - but passport not accepted. Sad, but important work to do here."
Khatib had previously told CNN: "If we win this award, it will show people across Syria that people around the world support them. It will give courage to every volunteer who wakes up every morning to run towards bombs.
"If I cannot enter the US, I will not give up: we know that we have many friends in US, that there are people that share our humanitarian values.
"I look forward to meeting them all one day."
He is not thought to have been affected by US President Donald Trump's travel ban, that was suspended by the courts days after it was put into effect.