Chicago sixth-graders Jack and Ruthie return to the Thorne Rooms at the Art Institute of Chicago and once again go back in time while trying to stop an art thief from endangering the miniature rooms.
A magical coin coin leads sixth-graders Ruthie and Jack to 1753 Massachusetts and to Jack's pirate ancestor when they return to the Art Institute of Chicago's miniature Thorne Rooms on a mission to restore an African American family's reputation.
In the Art Institute of Chicago's miniature Thorne Rooms, the Thorne Rooms key and a mysterious set of rings lead Ruthie and Jack to new historical eras and a woman who went missing as a young girl.