Director Asghar Farhadi's 8th feature premiere's in Cannes and goes on general release in France on the following day.
In the film, Laura (Penelope Cruz), her husband and children take a trip from their home in Argentina to her native village in Spain for a family occasion that turns into a family intrigue.
After making films in his native language and in French, Farhadi turns to Spanish for Todos Lo Saben.
This is the first opening film at Cannes in a language other than French or English since 2004, when another Spanish-language film, Pedro Almodvar's La Mala Educaçion occupied the opening slot.
As has already been the case on some occasions, it is competing for the Golden Palm award.
Farhadi's films have a track record at Cannes. In 2013 the female lead in The Past, Bérénice Béjo, won the Best Actress Award and Shabab Hosseini won Best Actor in 2016 for The Salesman.
The Salesman alsowon the US Academy Oscar Award for the Best Foreign Film. At the Berlin Film Festival, Farhadi's A Separation won the 2011 Golden Bear.