When Man Was YoungPaperback, 10 February 2021

Ken Sasaki and his fellow time-travelers paid well for the Neanderthal experience-two weeks living with an Ice Age tribe, becoming part of that tribe. Things did not quite work out that way. The last minute addition of a woman scientist to their group caused some grumbling. That proved to be the least of their problems as they found themselves struggling for survival in an inhospitable world, an age ago, When Man Was Young.