All across the contemporary world, space whales are falling from the sky. They seem to be trying to deliver a message to the Earth — but as an American grassroots movement attempts to communicate with these creatures, it will face challenges from the government as well as the possible dangers of interacting with these interstellar beings.

A scientist collecting samples on Titan finds the expedition to be beyond her wildest dreams—and her darkest nightmares—when she connects with disembodied alien life. Their strange communications take on new urgency when both their lives are at risk.