It's the middle-grade team-up of the century as the heroes ofNew York Times bestselling author Ben Hatke join forces to save the world inMighty Jack and Zita the Spacegirl.Jack and Lilly are no strangers to heroics. They’ve befriended dragons, battled giants, and even earned the loyalty of a goblin army. So when they meet Zita the Spacegirl, fresh from her interplanetary travels and seeking their help to face a new threat, they’re more than ready for another adventure.But the