“When I saw you I fell in love, and you smiled because you knew.” — Arrigo Boito

Remember falling in love? We remember the girl, the boy, the place. But when was the last time we fell in love with a movie? For this writer, it was “The Third Man,” “A Place in the Sun.”

This summer it’s Olivier Nakache and Eric Toledano’s “Samba,” a love story in two colors. Maybe it’s the season, an old man’s nostalgia tic, but I think it’s mostly because of the cast.

Alice (the mesmerizing Charlotte Gainsbourg, “Melancholia”) had a fine job with great promise and equal stress that drove her to the brink of a nervous breakdown. She took an extended leave of absence and spent her days fighting depression and swallowing multiple brands of sleeping pills.

To ease her way back into the workaday world, Alice volunteers in a Paris immigration office, where she is broken in by her cynical street hardened co-worker, Marcelle (a delightful Helene Vincent.)

Alice’s job is to help move along the flood tide of immigrants from all corners of Europe, Africa and Asia, who are flowing into France, a task comparable with keeping the Mississippi from entering the Gulf of Mexico.

On day one, Alice is left alone in her first hour to deal with Samba, (Omar Sy from the magnificent “Intouchables.”) Samba, a gentle giant, pure of heart and soul, is an illegal immigrant and refugee from Senegal, who has been in Paris for 10 years, working in kitchen prep. He is happy and close to achieving expertise as a chef. He lives in a tiny apartment with his sweet, old uncle who has survived here for much longer. By now, Samba is worn out from the constant stress of walking the mine field of avoiding attention, but he needs to work to send money home to his mother.

Alice has been warned not to get close to her clients, to stay aloof. We, and Alice and Samba know from the moment their eyes and souls meet, that this rule will go out the first open window it comes to.

These two stars are so compatible, so perfectly cast, and the script, by writers Delphine Coulin (novel) and Muriel Coulin, so skillfully woven, that we adopt them at once, taking them to our hearts while praying that nothing goes wrong on this ride.

At his first meeting with Alice, Samba has been caught up in the immigrant net and lost his job and is being held. Alice takes his case getting him a reprieve, but it’s only temporary.

Their journee du coeur begins, and weaves through the modern emotional traffic of a beleaguered and impersonal Paris.

As in all romances, the ups and downs are stomach wrenching. Samba gets part-time jobs, one as a security guard, where he is mugged and runs afoul of the cops, another that bonds him with an immigrant mate “Wilson” (beautifully played by Tahar Rahim) from South America. Or is he? In one hilarious scene, Wilson gets Samba a job alongside him as a window washer on the 89th floor of a building. Here, Wilson does a jazz strip with a room full of secretaries, while a terrified Samba holds on for dear life. You will dance in the aisles with this scene.

The arc of the story does follow the predictable path of ups and downs, close calls and near misses, especially in one heartbreaking incident near the end. But despite the rain, the cops and the quicksands of bureaucracy, love prevails. This is after all, Paris.

The simple purity of Omar’s Samba, the total light of Gainsbourg’s Alice, and the infectious rascality of Tahar Rahim’s Wilson adds another glow to the city of light.

J.P. Devine is a former stage and screen actor.