After their first adventure united Miri and Molly as twins in the 21st century, the pair discover more about the magic of time travel via doorways and other openings in their house. Unfortunately, their twin brothers also go traveling, getting into hot water in 1864 Virginia.

As a middle child stuck between two sets of twins, eleven-year-old Miri Gill feels an outsider until one day in her attic room, she slips back in time from the 21st century to 1935 where she meets Molly, another eleven-year-old who needs her help.

Also in need of some help is the model of time travel in the story, which is a mishmash of popular representations that no person at age eleven or elsewhen should be exposed to. Specifically, I would have enjoyed an attempt to square the Branching Timeline implied by the hole in floor with the single nonbranching, static timeline and Ex Nihilo paradox hinted at by the time-travel device. I truly liked that ex nihilo paradox, and wish it had been explicitly dealt with rather than swept under the carpet.