At this point, there are several things you’re almost sure to encounter when diving into one of Ryan Murphy’s gilded television worlds. No matter where or when it’s set, the show will have impeccable, eye-popping costume and production design. No matter how it unfolds, it will do its damndest to shock and awe, probably by putting characters through an incredible amount of psychological and/or physical distress. No matter what it’s about, it will feature several deliciously dramatic turns from actors ready to chew up and spit out every ounce of scenery they get. His new Netflix drama “Ratched” ticks off every one of these boxes and then some with the kind of gory flair that Murphy’s leaned into for projects from “Nip/Tuck” to “American Horror Story.” It even stars his muse, Sarah Paulson, in a role that requires her to be flinty, cruel, compassionate and lovelorn all at once. But as an ostensible origin story for Nurse Ratched, the towering villain of Ken Kesey’s “One Flew Over the Cuckoo’s Nest,” “Ratched” is a confusing character study that never quite gets a grip on the character it’s studying.