All his life, Harold Fry did nothing extraordinary, living an ordinary life with his wife in a small English town. One day he receives a letter saying that an old acquaintance has been diagnosed with cancer and has been admitted to a hospice. Harold writes him a letter, but then, out of a sudden impulse, decides to deliver it in person, walking the 800 kilometres to do so. Harold makes the news, becomes a sensation, and is followed by occasional followers and supporters. In the process, he comes to know himself better and takes stock of his life.