Wagner’s Ring cycle, as imagined by the Lyric Opera of Chicago, is a challenge in ways that go far beyond the musical complexities of the score. Some scenes, for instance, take place underwater, which many companies are content to leave as an implied setting, but which the Lyric has decided requires its Rhinemaidens to perform while suspended from bungee cords. The resulting midair dance is a wonderful sight to behold, but behind the scenes, it is one of the more complex staging endeavors ever mounted on the operatic stage, requiring not only split-second timing, but serious teamwork.