Professor Samuel O'Shea (Gabriel Byrne) teaches poetry at McGill university, but when a lifetime of alcoholism leads him to begin having hallucinations, he goes to see a doctor. Following an MRI, he discovers he has a large, inoperable tumor in his brain that will kill him within the year.

Knowing that he's been a terrible father to his son (Antoine Olivier Pilon) and daughter (Karelle Tremblay), he tries to make it up to them, while writing a book about his life growing up without a mother, and losing his father at a young age. He travels back to his homeland of Ireland, where the hallucinations continue, but all of his experiences and his visions of his father Ben (Brian Gleeson) as a ghost become content for his book.