In a once-in-a-lifetime event, 3A performs composer Philip Glass’s one-act sci-fi melodrama beneath the towering Spruce Goose’s tail, commemorating the 75th anniversary of its lone 26-second flight. Set in NYC, the sole character, “M,” recalls encounters with extraterrestrial life forms. Are the surrealistic visions haunting her an accurate recollection of an abduction, part of a drug-induced nightmare, or the beginning of a mental breakdown? M mirrors builder Howard Hughes’s own mental battles at this nexus of the fragile mind and sky.