"To a Land Unknown", directed by Mahdi Fleifel, follows two Palestinian refugee cousins around Athens as they try to save up money to pay a smuggler to sneak them into Germany.
Chatila has left a young family behind in Lebanon to try to keep his fragile cousin Reda sober and away from their squat's poet drug dealer long enough to gather the cash.
But the odds are stacked against them, forcing Chatila to lay aside his principles one by one as he devises increasingly dangerous schemes to try to save himself and his cousin -- even at the expense of fellow migrants.
First-time actor Aram Sabbagh plays the Palestinian character of Reda, whose family fled the 1948 creation of Israel to end up in a camp in Lebanon.
"It's important to come and leave a Palestinian mark" in Cannes, he said.
He described a feeling of constantly roaming in search of a land "because they stole our country".
"The curse is that you're pushed to want to leave but you risk dying before you arrive or even dying before you've left," said the 26-year-old actor, who grew up in Ramallah in the occupied West Bank.
"You tire yourself out running against the clock but in the end you... haven't left or stayed, you're just stuck in time."
'Real migrants'
Fleifel's fiction film follows his 2012 long documentary "A World Not Ours" portraying several generations growing up in a refugee camp in Lebanon.
The Palestinian-Danish director later followed one of the characters from the camp in Athens in a short documentary called "Xenos", in which he says that desperation sometimes pushes him to prostitution to avoid stealing someone's handbag.
Sabbagh said he prepared for the role by watching and speaking to migrants in the Greek capital during the shoot.
"We were in an area that was full of migrants," he said.
"We had extras in the film who really were migrants stuck in Athens."
Sabbagh, who also brought his skateboarding skills to the role, said he often nagged his co-star Mahmood Bakri -- who hails from a famous Palestinian thespian family and plays Chatila -- for acting tips.
Bakri, a 27-year-old who studied cinema in Bethlehem, said that for him too it was important to be in Cannes as a Palestinian actor at the start of his career.
But he said he was finding it hard to join in with the festivities with the war ongoing in Gaza.
"I don't really feel like I'm in its mood," he said.
