When Tony Lip (Viggo Mortensen), a bouncer from an Italian-American neighbourhood in the Bronx, is hired to drive Dr Don Shirley (Mahershala Ali), a world-class black pianist, on a concert tour from Manhattan to the Deep South, they must rely on The green book to guide them to the few establishments that were then safe for African-Americans. Confronted with racism and danger – as well as unexpected humanity and humour – they are forced to set aside differences to survive and thrive on the journey of a lifetime.

The controversy surrounding this film should not dissuade people from watching it. (Google if you must.) It is a nuanced, tender tale about an unlikely friendship that overcame loneliness, bigotry and class differences. Viggo Mortensen and Mahershala Ali’s performances appear effortless.

This is Viggo Mortensen’s best performance since A history of violence (yes, not Lord of the rings). He personifies the coarse, yet affable, Italian working-class patriarch that wins hotdog-eating competitions, bounces brawlers out of the Copacabana, and then returns home to his doting wife and kids. When he is at his most offensive and brutish, you still root for him as you witness his slow transformation.

Mahershala Ali, on the other hand, seamlessly slips into the gentle charm, musical genius and brittle loneliness of the real-life Don Shirley, of the Don Shirley Trio. There is a vulnerable element in this performance that reminds me of his turn as Juan in Moonlight.

Even when he is at his most brisk and judgemental, you respect him. Mahershala, instead of preaching to you, manages to make you feel just how vulnerable people of colour are in certain situations. If this film does not move you, you are made of stone.

There are small moments of beauty and moments of gentle humour, often intertwined, moments that only strengthen this gentle film.

The music, especially, but also the faded cinematography/colour grading and styling, only add to the allure of the film. It certainly made me want to dust off the old road map, put together a playlist and cruise down the highway.

Sure, the script, penned by Nick Vallelonga (real-life son of Tony Lip), romanticises both the men and their friendship. I am okay with that. It tells a tale worth telling, and it does it with charm and sincerity.