Alas, Agent Mark Davis has misinformation. Tickets to the Spy Museum are good for 24 hours. You can leave and come back as many times during that time span. For more information or tips for visiting the new Museum, check out spymuseum.org or call: 202-393-7798.
The answer is no. Once in the Museum, it's one and done. No re-entry.
I don't believe so, but I'm not a hundred percent sure
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