Becca and Maddie, preteen sisters and unlikely experts of time travel, need adult supervision as they travel to Nashville in August of 1920 to fix the timeline. So they take along Philip, a time travel expert from the future who happens to be responsible for breaking the timeline in the first place.
But the only way to get from Seattle to Nashville is by train, and the time travelers arrive in Nashville too late to stop Douglas Whitfield, aka Mr. Selfish, from stealing a letter intended for one of the legislators. The theft of a single letter seems a small thing, except this particular letter plays a pivotal role in history. Without it, the Nineteenth Amendment is not ratified, and women never have the right to vote in the United States.
Amid a contentious backdrop that some have called the War of the Roses, and others the Perfect 36, Becca, Maddie, and Philip must fix what is broken before Mr. Selfish can break the timeline for good.
It isn’t easy, but the time travelers eventually succeed in setting history right. They capture Mr. Selfish and return to the portal to be reunited with their families.