Michael and Derek don't expect the adventure of a lifetime visiting a Civil War museum with their grandmother. But the mysterious museum keeper invites them to play a game, and before they know it, they're walking through a door straight into a very realistic depiction of 1863. They see the destruction at the battlefield of Antietam, and even meet President Lincoln. Soon, they start to wonder if it's really a game, after all-and suddenly they're racing across Confederate-occupied land to return to their own time before it's too late. Patricia Polacco's time-travel premise is fascinating- who knew that history museums could literally be doorways into the past? She makes history exciting for young readers, drawing them into a pivotal part of our nation's development.