Something terrible is happening to Benjamin's family. At first it's almost too subtle to notice. His mother just doesn't look as attractive as usual and his father looks mean. The situation gets worse. Family members get sicker and sicker. Terrified, they consult every doctor they can, but no one has any idea what is causing the mysterious illness. The only way to save Benjamin's family is to go back in time and undo an evil deed done by a member of Benjamin's family many, many generations ago. Benjamin and his friend morph into famous figures from the past. The boys go deeper and deeper into centuries long gone—becoming such renowned men as Abraham Lincoln and Ulysses Grant, Julius Caesar and Marc Antony—as they race against the clock to save Benjamin's family.