An injured whooping crane appears out of thin air at the Sewanee Sanctuary in rural Wisconsin. The sanctuary trains whooping cranes how to migrate along the eastern part of North America. The appearance of the bird is just the first strange appearance of beings and artifacts from other places and times, however. The mystery brings together an unlikely group of scientists who seek to understand the phenomenon. They find themselves racing against an emerging deadline and fighting the resistance of government officials who fail to comprehend the stakes. Finally, they take matters into their own hands in an attempt to avert disaster.