For his version of “Frankenstein” — the movie he was clearly born to make — Guillermo del Toro leans hard into “Paradise Lost,” with his own twist. Del Toro’s lifelong obsession with the story began in childhood, and he loved watching Boris Karloff portray the creature in the classic 1931 film, the one most of us still think of when we think about Frankenstein. Like generations of readers and audiences — “Frankenstein” was first produced for the stage in 1823, only five years after the novel’s first publication — del Toro was drawn to the pathos, the tragedy, the strange beauty of the tale.