Cosmic rays of energies >10²⁰ eV are not expected to "exist"…but they do! While this popular "who dun it" is not yet on the New York Times best seller list, hundreds of astro-physicists and particle physicists are "on the case". The talk will provide the background information, summarize the cast of characters, reveal the "Dark Side" experiments, describe the how and where, and then report some recent clues.