After his brother, Joe (Chandler), suffers a heart attack and dies, Lee Chandler (Affleck) returns to his sleepy little hometown of Manchester-by-the-Sea to handle the funeral and be with Joe's teenage son, Patrick (Hedges). He is shocked when he learns that his brother, not wanting to leave Patrick in the care of his alcoholic ex-wife (Williams), has named Lee as the boy's guardian, and he begins to make plans to take Patrick back to Boston with him. Patrick, still reeling from his father's death, doesn't want to leave, but with darkness lurking in his own past in Manchester-by-the-Sea, staying long isn't an option for Lee's tormented soul.
During World War II, devout Seventh-day Adventist Desmond Doss (Garfield) signs up for the army, despite being a conscientious objector, in this true story. During his basic training, he is bullied due to his refusal to train on Saturdays or to handle a weapon, ultimately leading to his arrest for insubordination. After being released by the courts, he reunites with his unit, which is assigned to a hot spot in the Pacific. Along with his fellow soldiers, who hate and ridicule him, he faces off against a formidable and deadly enemy, and his actions ultimately lead to him becoming the first conscientious objector to be awarded the Medal of Honor.
More than a decade after their failed Christmas heist, Willie (Thornton) and Marcus (Cox) reunite to pull off a new con job in Chicago that's been set up by Willie's mother, Sunny (Bates). Willie and Marcus set up a secret deal to betray Sunny once they've secured the millions of dollars they're hoping to score, and Willie, once again, takes on the role of Santa. As they infiltrate the charity that they're targeting, though, the plan begins to unravel in spectacular fashion.