His world shaken, Gus runs off and makes a rash decision. Big Man comes to grips with long-ago mistakes. Aimee makes a last stand against General Abbot.

In a moment of desperation, Dr. Singh makes a bold promise. A lost memento makes for a bumpy ride to Colorado. The Last Men close in on the Preserve.

Gus and Big Man pick up a traveling companion who suggests a perilous shortcut. Aimee’s sanctuary comes under threat. Time’s running out for the Singhs.

Gus lands under the protection of some new friends as Big Man’s past catches up to him. Dr. Singh fears a nosy neighbor will unearth Rani’s secret.