... (Chris O’Dowd), loyal friend to Vincent finds out that his friend shot himself somewhere up North. He has in his possession a letter from Vincent to his beloved brother, Theo, which was returned as undeliverable. On hearing the news about Vincent he sends his hot-blooded son, Armand Roulin (Douglas Booth), on a mission to deliver the letter by hand to Theo and find out what really happened to Vincent.
Armand is a reluctant detective, not much caring for his father’s erratic erstwhile drinking companion. After having witnessed Vincent on the night he cut off his ear Armand can all too easily imagine the unstable Vincent taking his own life. But his father insists, so he heads to Paris.
In Paris there is no sign of Theo. He is directed to Pere Tanguy (John Sessions), the paint seller.