Kenneth Lonergan, who wrote the movie Manchester by the Sea, shapes his work from loss, disillusionment, small-mindedness, hesitation and superficiality, all the forgettable detritus of life. The Starry Messenger is about Mark, a disappointed astronomer aged 52, who gives public lectures at a city planetarium. He loves his subject even though it let him down and every week he tackles the daft questions of his pupils with superhuman patience.