Mari and Waka plan on making a cake, but plans fall apart when Mari opens a mysterious book that sends her flying back in time.

Mari hangs out with Dr Gilbert while he discusses theories about the Earth's magnetism. Meanwhile, Waka and her brother look through Mr Hayase's lab for any trace of Mari.

A lesson about Ben Franklin leads Mari to meet the man himself as she assists him with the kite experiment.

Mari encounters an unexpected guest of Alessandro Volta and discovers some more details that could lead her to her father's location.

Waka's wish to travel back in time is fulfilled, but things do not go exactly the way she had expected.

While Waka is still trapped in 19th century London, she is taught a valuable lesson about dedication and moving past failure.