Grieving mom Frances Cairnes (Cush Jumbo) opens “The Beast Must Die” with these chilling words: “I am going to kill a man.”And, from there, the six-part thriller shifts into maximum overdrive.Premiering Monday (July 5) on AMC+, it’s based on the novel by Nicholas Blake — aka Poet Laureate Cecil Day-Lewis (the late father of three-time Oscar winner Daniel Day-Lewis) — and was shot on location on the Isle of Wight, about a 20-minute ferry ride from the south coast of England. That’s where Frances’ six-year-old son, Martin, ran out of sight one Easter Sunday and was killed on a winding road by a hit-and-run driver, who was never apprehended.
