Finn always knew life had its ups and downs, but he had learned quick that the key to happiness lay in getting up again. Marceline had been smacked down so many times, down became a kind of up in itself. Two fates, the last products of a wonderous bygone age, battle together for a reimagined destiny in the Land of Ooo. AT takes to the stars in an epic sci-fi shakeup.

Thrown from place to place, a scar on time itself, Marceline once again senses the need to move from her present surroundings. But a certain kind-hearted weirdo who wears a bear hat isn't about to let her drift into emptiness forever, even if it means exploring her past; a very dangerous adventure indeed.