Set in a colorful yet gritty 1970s Boston, "Free Fire" opens with Justine, a mysterious American businesswoman, and her wise-cracking associate Ord arranging a black-market weapons deal in a deserted warehouse between IRA arms buyer Chris and shifty South African gun runner Vernon. What starts as a polite if uneasy exchange soon goes south when tensions escalate and shots are fired, quickly leading to a full-on Battle Royale where it's every man (and woman) for themselves.