Very, very, VERY big plot bomb. Jaw-dropping for the writer looking at the mass of Story that just exploded into her head and is wondering how the heck to write it as well as it deserves. This one covers a lot of ground, temporal and geographic.
All praise to the Plot Daemon, who has outdone himself. (“All right, all right, lassie. Now will you just go back up there and steer?”)
(Back to work.)