The night after the Extinction event is prevented, Sam's body is kidnapped, his soul still at the Beach. The same night, an unexplained event reverses timefall, locking the world into a loop. With the world frozen but humanity living on, supplies will dwindle, and it'll be up to an odd pair to find out where Sam's body is and find way to bring the world out of its time loop.
No one can dictate fate. He thought the world was his to destroy, and she wanted to save it. Who knew she'd soon change her mind?