After the death of his older brother Joe, Lee Chandler (Casey Affleck) is shocked that Joe has made him sole guardian of his teenage nephew Patrick. Taking leave of his job as a janitor in Boston, Lee reluctantly returns to Manchester-by-the-Sea, the fishing village where his working-class family has lived for generations. There, he is forced to deal with a past that separated him from his wife, Randi (Michelle Williams), and the community where he was born and raised.