The Grimm tale “The Robber Bridegroom” is KHM 40.
In the story, a young woman is betrothed to a wealthy suitor who lives in a forest house. Suspicious of him, she marks her route with peas and lentils rather than relying only on the ash trail he provides. At the house, she discovers a murderous band of robbers and hides with help from an old woman.
The heroine escapes after the robbers are drugged. At her wedding, she presents the terrifying events as a dream, then reveals physical evidence—including a severed finger bearing a ring—to identify the bridegroom and his accomplices. They are subsequently executed.
The tale is number 40 in the Grimms’ collection and is classified as Aarne–Thompson type 955. It is closely related to “Bluebeard,” “Fitcher’s Bird,” and other stories about dangerous bridegrooms. Editions also differ: the 1812 version features a prince and princess, while the 1857 version uses a miller’s daughter and a rich suitor.