They started as a wedding gift for Yoko Ono and a "bit of fun," but as occasionally tended to be the case with John Lennon's ideas, his series of erotic sketches -- dubbed 'Bag One' and enshrined for display at the London Art Gallery on Jan. 15, 1970 -- attracted a whole bunch of controversy.

In fact, on only the second day of the exhibition, Scotland Yard officers raided the gallery and confiscated eight of the 14 prints on display, citing "the great influence of John Lennon as a Beatle" to "deprave or corrupt" unsuspecting visitors.

"Many toilet walls depict works of similar merit," clucked Detective Inspector Frederick Luff, who'd earned a reputation as a specialist in "celebrity raids." "It is perhaps charitable to suggest that they are the work of a sick mind."

Fortunately for Lennon, the magistrate who presided over the case several months later wasn't so easily convinced. Asking Luff for evidence that anyone was genuinely offended by the exhibit, John Harmsworth engaged in a bit of humorous back-and-forth with the detective. "I saw no display of annoyance from the younger age group, but one gentleman was clearly annoyed," admitted Luff, to which Harmsworth quipped, "Did he stamp his foot?"

The case was ultimately thrown out after Harmsworth determined that the images were unlikely to "deprave or corrupt," but 'Bag One' wasn't finished raising the ire of would-be guardians of societal decency. The collection finally received a 100-city worldwide tour in 1981, and although things went quite a bit smoother than they had in 1970, organizers ran into trouble in Rhode Island, where the police department closed the show on grounds of obscenity.

Tastes change, however -- and Luff would presumably be disappointed to learn that today, 'Bag One' has taken up permanent residence at the Museum of Modern Art in New York -- and images associated with the collection have been known to sell for impressive sums on the auction market.

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