Oleg Sentsov, an internationally-recognised film director who has previously been detained by Russia, is now fighting for Ukraine.
Sentsov has always been politically active: he took part in the 2013 Maidan uprising that ousted a pro-Kremlin president in Ukraine and then joined demonstrations in his native Crimea, a Black Sea peninsula that Russia annexed from Ukraine in 2014.
Later the same year, the director of the internationally acclaimed film "Gamer" (2011) was arrested by Russia and sentenced to 20 years in jail on terrorism charges.
Thrown behind bars in Siberia, Sentsov staged a hunger strike for 144 days before he was released in 2019 as part of a prisoner swap between Russia and Ukraine.
His jailing was met with international outcry and sent shockwaves through the cinema world with European directors such as Pedro Almodovar and Wim Wenders appealing for his release.
While behind bars in 2018, Sentsov was awarded the European Parliament's Sakharov Prize for Freedom of Thought.
Just last year, he was presenting his socially gritty gangster film "Rhino" at the prestigious Venice film festival.
"I had some rest in a Russian prison, afterwards I returned to cinema, and now I'm in the army. I don't know what I will do in 10 years after that because I have changed my life many times," said Sentsov.
"Russia wants to take back their old colony of Ukraine," he added, "but Ukraine is not a colony. Ukraine is an independent country and has a very brave nation who will fight against any aggression."
Sentsov took up arms after moving his family to safety in the western city of Lviv.
Ukraine will prevail, he says, because it's fighting for its existence.