Bacri / Jaoui

Jean-Pierre Bacri and Agnès Jaoui are a famous French movie dirctor/writer couple. After the success of their play Cuisine et dépendances, that showed the dynamics of a mundane dinner from the kitchen where people meet "backstage" to discuss personal confilcts, they went on to write others, and started adapting them for the big screen, with as much success, and often starring in their creations. Nowadays, while Jaoui focuses on her career as a director, Bacri is still known for his roles of depressed/sad/angry characters that he excels at.
Their latest creation, Comme une image, falls right into that category. And this time it's even playing in US theaters under the title "Look at me".

sage = wise / well-behaved
sage comme une image = to be well-behaved ("to be as quiet as an image")