Haskel Yngren and Jennifer Jessup, along with Jennifer's long dead parents, travel sideways through time experiencing other realities that diverge from their own.
If, on the coldest night of an uncommonly cold Minnesota winter, you should meet a person in a busy intersection wearing only shoes and stockings and sporting a large brass spittoon pulled down over his head, and if you should recognize him as your own sweet self, we will forgive your momentary confusion.
You may require some time even to phrase the question, "How can this be?" With no easy answer you may believe you are dreaming, but if you pinch yourself and do not waken you must seek other answers.
Hallucinations, if you are not mad, and visions, if you are not religious, are insufficient and unsatisfying explanations. You may consider the possibility that you have been transported to a parallel universe. But we cannot expect you to guess the truth: that there are more diensions of time and space than you have faculty to comprehend and that, to effect this rendezvous, you have traveled sideways through time.