We saw the trailer and heard the song — a sweet, winsome cover of Neil Young's "Heart of Gold" — and now it's here. Director Jonah Ansell's animated short Cadaver tells the story of a medical-school cadaver (voiced by Christopher Lloyd) who suddenly reanimates as a student (Tavi Gevinson) begins to dissect his body, setting in motion a journey that ends in heartbreak. With Kathy Bates as a flirtatious older woman.