Beneath the polished guise of Smithsonian respectability lies a quirkier side of Washington, D.C., museum life. Check out these off-the-beaten-track museums in the U.S. capital.

International Spy Museum

Assume a secret identity at the only museum in the world dedicated to espionage. Learn the importance of keeping your “cover,” undergo training at the School for Spies (where you’ll discover microdots, buttonhole cameras and more), and explore the vast global history of reconnaissance throughout the centuries. Don’t miss James Bond’s Aston Martin or the lipstick-container-turned-gun used by female KGB agents.

National Museum of Health & Medicine

Founded by the U.S. Army during the American Civil War, this is one of the country’s oldest museums. Marvel at its millions of medical oddities — everything from a stomach-shaped hairball (extracted from a girl who ate her hair) to the bullet that killed U.S. President Abraham Lincoln in 1865.

National Bonsai and Penjing Museum

If plant life is more alluring, check out this collection of 200-some miniature tree masterpieces — all perfectly pruned. Among the beautiful, intricately shaped plants is a 400-year-old Japanese White Pine bonsai that survived the bombing of Hiroshima in World War II. The bonsai was gifted by a Japanese gardener in 1976, in celebration of the American bicentennial.

National Museum of Crime & Punishment

Ever wanted to test your Wild West shooting skills? See if you could outwit a polygraph machine? Try your hand at forensic science in a crime scene lab? Check out the Crime Museum, with hundreds of interactive elements and crime-related artifacts. You can even see a portrait of yourself added to the “Most Wanted” list — an image that will stick with you, for sure.

The Museum of Unnatural History

Dedicated to the discoveries of the Unnaturalist Society, this “museum” showcases the rarest of the rare and other playful, imaginative wonders — including unbelievable animals like weagles and owlephants. As part of a nonprofit co-founded by creative mastermind Dave Eggers, the museum serves as a storefront to support in-house tutoring and writing programs for kids. Don’t leave without buying some Unicorn Tears or those pesky “Missing Links” that evolutionary biologists have spent their careers hunting.