In late 2017, scientists at a Hawaiian observatory glimpsed a strange object soaring through our inner solar system. Astrophysicist Avi Loeb conclusively showed it was not an asteroid; it was moving too fast along a strange orbit, and leaving no trail of gas or debris in its wake. There was only one conceivable explanation: the object was a piece of advanced technology created by a distant alien civilization. Inside the thrilling story of the first interstellar visitor to be spotted in our solar system.