2018 Carolyn W. Field Award Honor Book 2018 Sydney Taylor Honor Book for Teen Readers When sixteen-year-old Ellie Baum accidentally time-travels via red balloon to 1988 East Berlin, she's caught up in a conspiracy of history and magic. She meets members of an underground guild in East Berlin who use balloons and magic to help people escape over the Wall―but even to the balloon makers, Ellie's time travel is a mystery. When it becomes clear that someone is using dark magic to change history, Ellie must risk everything―including her only way home―to stop the process.

Siblings Ilse and Wolf hide a deep secret in their blood: with it, they can work magic. And the government just found out.Blackmailed into service during World War II, Ilse lends her magic to America’s newest weapon, the atom bomb, while Wolf goes behind enemy lines to sabotage Germany’s nuclear program. It’s a dangerous mission, but if Hitler were to create the bomb first, the results would be catastrophic. When Wolf’s plane is shot down, his entire mission is thrown into jeopardy. Wolf needs Ilse’s help to develop the magic that will keep him alive, but with a spy afoot in Ilse’s laboratory, the letters she sends to Wolf begin to look treasonous. Can Ilse prove her loyalty—and find a way to help her brother—before their time runs out?