Brent Lang Executive Editor of Film and MediaFor Richard Jenkins, breaking into the movie business took years of rejection, bit parts and relative obscurity.But Hollywood eventually came calling in the 1990s and Jenkins has been in demand ever since, logging impressive performances in everything from “Step Brothers” to “Six Feet Under” to his Oscar-nominated work in “The Shape of Water” and “The Visitor.” He may find himself back in the awards race with “The Humans,” a big-screen adaptation of