“You’ve made a career out of bodies.” Though this line is meant for Vincent Cassel’s character, Karsh, it could just as easily apply to the man who wrote it. David Cronenberg has indeed made a career out of bodies, transmogrifying many through slimy prosthetics as in “The Fly,” exploring their cavernous depths through sociological and psychosexual means as in “Eastern Promises,” often finding ways to blend the two into new, mysterious wholes as in his 2022 film, “Crimes of the Future.” In “The Shrouds,” Cronenberg has found a new, dark and perverse way to continue making his career out of bodies. “The Shrouds” follows Karsh, a Canadian tech mogul whose newest invention, GraveTech, allows mourners to peer into their loved ones’ graves to watch their bodies decompose. Karsh is obsessed with tracking the decay of his late wife, Rebecca (Diane Kruger), and consults her twin sister, Terry (also Kruger), after finding a lump on one of her bones. Soon after, Karsh’s cemetery, where GraveTec...