During the elimination of the Belgian/French border in the 90s, a Belgian customs officer is forced to team up with one of his French counterparts.

Over this long hot summer, Claude and Isabelle get their marriage back on track, while Bibou and Simon, spend a memorable summer discovering the world of grown-ups.

Alex, Antoine and Manu meet Jean, a loner who ignores the pleasures of friendship. Little by little, they learn to know each other, to appreciate each other. Jean is moved by the complicity and affection that fuels the relationship with his new friends.

A look at the life of French designer Yves Saint Laurent from the beginning of his career in 1958 when he met his lover and business partner, Pierre Berge.