That's the fun premise of this thrill-filled series--which has story panels and speech balloons just like a graphic novel--that journeys from primeval Los Angeles (where mastodons and saber-tooth tigers still roam) to Jerusalem during the Crusades. The excitement begins when Oz invents a state-of-the-art time machine that takes him and his friend Elspeth hurtling through the centuries. But there's a catch: Oz's invention only works when he enters...