The 15th novel in the New TOM SWIFT Invention Adventures. Just two years ago Tom Swift and his best friend, Bud Barclay, journeyed through a wormhole and nearly lost their lives investigating a black hole. After returning Tom sent an unmanned probe back there to keep an eye on things. The time has come to replace it. But, when he does the first videos sent back reveal something so startling that Tom isn't certain what to believe. The probe shows him something Tom knows had to be in the past. What might it mean? The first thought he has is some sort of time fluctuation has occurred. He is hesitant to refer to it as "time travel." But, what if that is exactly what it is? Is it something that can be replicated and used on Earth. Or, can the source of the phenomena be taken from its location back to Earth? Tom can only imagine the possibilities and sets out testing in until a personal tragedy forces him to try something radical.