A Matter in Time — Michael Faris

The crew of the airship Judy has finally found the magical talisman it has long sought--and escaped from those who also seek this object, The Dooda, for their own purposes. But their escape brings additional danger. While the power of The Dooda has helped them escape their captors, that escape has also carried them out of their own world--at least out of their world as they knew it. While the geography remains the same, the people are missing. Surviving in a strange land, and ultimately learning enough of The Dooda's secrets to return home is a critical mission. As the crew explores the power of The Dooda, though, they learn that simply surviving is not enough. Bringing the Dooda back to their own timeline won't eliminate the danger that The Dooda has opened. In fact, there is already a Dooda-created path between their own universe and that of the warlike reggin. Unless they are able to do something, their entire world will soon be overwhelmed.