An adventure from medieval Cologne, 1445: Ten-year-old Johanna risks a lot to learn to read and write. She only has time for this at night, as she works as a maid for a merchant during the day. It's clear that she must keep her nighttime activities a secret. But when she tries to "borrow" a candle from the cathedral to practice reading, she catches a real thief - none other than the merchant's son's teacher. Now Johanna is in serious trouble.