“The Crystal Crypt” January 1954

Mars and Terra are poised to wage war against one another as a final ship leaves Mars for Terra. A Martian Leiter (a kind of military policeman) makes everyone aboard the ship submit to a lie detector test about a city destroyed by three saboteurs. All the passengers pass the test, so the ship is allowed to leave. Meanwhile, Bob Thatcher strikes up a conversation with a woman named Mara and joins her and two others for drinks in the lounge. Though fearful at first, the three concede to fellow Terran Thatcher that they are the saboteurs. They tell the story of how they shrank the city down and now carry it with them for ransom. It looks like a paperweight. Thatcher congratulates them on their ingenuity then reveals that he is a Martian Leiter. They will not be returning to Terra after all.