In the Irish village of Glenkill, George Glenn is a shepherd who is a loner, estranged from his wife, and is fond only of his sheep. Every day, after he lets them out to graze, he reads to them from romance adventure novels and textbooks on sheep diseases. At the start of the book, the sheep find George dead, pinned to the ground by a spade. The rattled sheep decide that they must find his killer. This turns into a difficult task, as sheep can’t talk to people; and though they understand the human conversations they listen in on, like the one between George’s widow Kate and Bible-basher Beth Jameson, they do not always understand the details. Not even the smartest of them, Miss Maple, Othello and Mopple the Whale, can understand the humans' behaviour, and are particularly confused by the neighbourhood priest, though they conclude that his name is evidently God. They are afraid to confront suspects like butcher Abraham Rackham, and are suspicious but fearful of their new shepherd Gabriel O’Rourke, who is raising a flock of sheep for slaughter. And even after a series of providential discoveries and brainwaves reveals the answer to the mystery, they still have to figure out how to let the humans know.