The Penny Black theft and the riddles it prompted was not presented as an isolated museum crime but as the opening move in a carefully coordinated stunt. By linking a false tip, rhyming challenges, and the planting of the missing item in Milo Motion’s copy of The Hollow Man, the thief turned a theft into a public locked-room puzzle aimed at both the police and the Bloodhounds.

Planning and Sequence

John Wigfull’s reconstruction placed the theft on the Friday morning of the previous week. The day before, the police had received an erroneous tip-off from Bristol, directed to Sergeant Plant. On the Friday came the first rhyming riddle, and that same morning the theft occurred. Wigfull argued that the timing was evidence of advance planning, rather than a sequence assembled after the fact.

In his account, the separate steps dovetailed: the tip-off, the riddles, the theft at the Postal Museum, and the later planting of the stamp in Milo Motion’s book. The plan depended on inside knowledge that Milo Motion would bring his copy of The Hollow Man to the next Bloodhounds meeting and read from it. The book’s famous chapter on locked-room mysteries supplied the precise setting for the reveal.

The Planting and the Puzzle

At the meeting, the missing Penny Black cover was discovered in the book as Milo Motion was about to read the relevant chapter aloud. The discovery made the theft theatrical: the stolen item appeared at the exact point where the gathering’s discussion of fictional locked rooms met a real mystery. Since the book had been aboard Milo Motion’s boat throughout the week, and the boat was kept locked, the planted item seemed to pose a further question of access.

The locked-boat circumstances initially made Milo Motion an obvious person to examine, but he came to the police at once and was cleared. John Wigfull said he had interviewed him at length and found no reason to believe he was responsible; Peter Diamond likewise said Milo Motion had satisfied him. The apparent security of the boat therefore sharpened the puzzle without establishing the owner’s guilt.

Purpose and Effect

John Wigfull distinguished the episode from an ordinary theft: in his interpretation, the crime was also a stunt, designed to make both the police and the Bloodhounds look foolish. He believed the thief had intended to return the stamp after the display, making its disappearance part of a challenge rather than an end in itself. He described the undertaking as high-risk and intricately plotted, emphasizing how the sequence had worked as planned.

The riddles and the planted item changed the meaning of the theft. The Penny Black was not simply missing; its disappearance and reappearance had been arranged to direct attention toward a locked-room problem and to expose the investigators to a performance staged on the thief’s terms. At the point of Wigfull’s explanation, however, his reconstruction established the design of the crime without yet naming its perpetrator.