Twenty-three years ago, the O'Dwyer brothers buried their mother. Tonight, they've buried another of her killers.

Ciarán believes they're doing God's work. Finnian believes in his brother. Together, they've left a trail of bodies, prayers, and copper pennies across Boston.

But tonight, inside the very church where their mother was laid to rest, their sacred ritual goes terribly wrong.

Two gunshots. Two pennies. One creaking confessional.

And you were never supposed to be there.