Sam Foster is a fairly typical modern American teenager who just invented a time machine. Sam didn't mean to bring back anything from his first trip to the past, but he returned home to 2005 with more than he bargained for, in the form of Meg Clayton, a spirited pioneer girl from Oregon.

Sam would be only too happy to obey Meg's demand that she be taken home at once, but he encounters technical difficulties -- and a stranger who may threaten more than just Meg's life.

A month after their first adventure together, Sam Foster and Meg Clayton travel back in time to medieval England in hopes of solving an historic mystery. From the start, however, things go wrong. They aren't dressed correctly. The locals use strange words and have thick accents. And they arrive almost thirty miles away from their intended destination!

When the steward of the village, Geoffrey, arrives in the nick of time to save them from some unfriendly locals, the worst of their troubles seemed to be over.

Unfortunately, they had just begun....

A homework assignment to write an essay about what his life might be like a few decades into his future should be an easy task for Sam Foster. After all, Sam is the inventor of a time machine. With his friend from the past, Meg Clayton, Sam journeys to the year 2040 to investigate his fate firsthand.

It doesn't take long for Sam to find information about his future self. Not only does he become a wealthy businessman, he makes a name for himself in the world of computer technology. It appears Sam is destined for fame and fortune. But the pair also discovers something about "Older Sam" that stuns them: Sam's future self died just five years earlier, at the age of 45.

Will Sam and Meg be able to stop this "future shock" from happening? Or is Sam's destiny sealed for all time?

When fifteen-year-old Sam Foster finds out that his mother is going to get remarried, his first reaction is shock. His next reaction is thinking that with the help of his time machine, he might be able to go back and prevent his parents from getting divorced in the first place.

When Sam recruits Meg Clayton, his friend from 1850, he finds her missing her extended family and friends in Boston. Meg is quick to agree to Sam's request for help, not telling him how much she wishes she could fix something in her own life...and that she has her own plans for change.

In this fourth book in the Partners in Time series, Sam and Meg attempt to manipulate his family history...but it soon becomes apparent that repairing a fractured relationship is extremely complicated. Each time they make a change, it results in a present world that is nothing like Sam ever dreamed -- or desired.

Will they ever be successful in fixing the past and mending the present? Or will Sam never be able to return home again?

Fulfilling a promise from their last adventure together, Sam Foster travels from 2006 back to nineteenth-century Oregon to visit his spunky friend, Meg Clayton. This time, though, Meg gets to choose where they will visit next, and she already has a place in mind: Kingston, Jamaica, in 1717.

The Clayton family farm in Oregon is in danger of being lost, and Meg seeks a priceless family heirloom to save it. That means traveling back to Jamaica to retrieve the treasure before it can disappear...even if the area in question is crawling with cutthroat pirates.

The two time travelers venture to this dangerous spot with the best laid plans...only to find them going woefully wrong from the start. Separated almost from the first, they are taken aboard different ships and faced with a litany of problems the history books never mentioned. Neither is prepared for the sunburn, seasickness, and squalor they experience, and their goal quickly shifts from finding Meg's heirloom to staying alive, reuniting--and returning home.

Will Sam and Meg's change of course help them return to the safety of their own time periods, or will they be marooned in the eighteenth century, left to live the rest of their lives with--or die at the hands of--a band of cold-blooded pirates?