Professor Childermass has made an astonishing discovery. Behind a bricked-up wall in his house is a rickety old trolley that can travel through time. Soon Johnny Dixon, his friend Fergie, and the professor are headed for Constan- tinople, 1453! The professor has a desperate plan to alter history, but it may cost him his life. Can Johnny and Fergie stop him before it's too late? Brace yourself for a wild ride. -- Kirkus Reviews The late John Bellairs was the critically acclaimed, best-selling author of many Gothic novels, including the novels starring Lewis Barnavelt and Rose Rita Pottinger.