What happens between book 9 of the Young Wizards series, A Wizard of Mars, and the forthcoming book 10, Games Wizards Play? Diane Duane answers the question in this volume, collecting together the three canonical works that constitute a "transitional trilogy" between books 9 and 10 -- a 150,000-word extravaganza of untold tales to help keep you going until the tenth book comes out in February 2016.
Interim Errantry contains:
The novella Not On My Patch, the tale of an unusual Halloween in the Young Wizards' neighborhood, featuring overage Trick Or Treating, suburban zombies, and the Attack of the Killer Pumpkins.
The novelette How Lovely Are Thy Branches, a holiday-themed Young Wizards story in which an alien wizard who looks a lot like a Christmas tree gets the gift he wants most -- decorations -- and a memorable party and sleepover are only slightly disrupted by a superblizzard and an incursion of otherworldly ghosts.
And finally, the new original Young Wizards novel Lifeboats, the tale of a distant world threatened by unavoidable doom, an intervention that takes thousands of Earth's wizards, young and old, into harm's way, and a Valentine's Day that absolutely doesn't go as planned...
(All three works are also available separately at Ebooks Direct in case you have (or have read) one or more of them but don't need to purchase it / them again.)