Secret arrive during the 1st Gaon Chart K-POP Awards at Blue Square on February 22, 2012 in Seoul, South Korea. (Photo by Chung Sung-Jun/Getty Images)

Coulpe in bed, secret lover hiding. (Photo by Peter Cade/Getty Images)

A performer from Cirque du Soleil's show “Quidam” practices backstage before a show at the MEO Arena in Lisbon December 18, 2014. (Photo by Rafael Marchante/Reuters)

Italian-American actress and model Julia Fox is seen on September 07, 2023 in New York City. (Photo by Rachpoot/Bauer-Griffin/GC Images)

Danielle Sellers attends The Beauty Awards at Tower of London on November 28, 2017 in London, England. (Photo by Lia Toby/WENN)

Model Adriana Lima attends Madonna presents An Evening of Music, Art, Mischief and Performance to benefit Raising Malawi at Faena Forum on December 2, 2016 in Miami Beach, Florida. (Photo by Jeff Kravitz/FilmMagic for Raising Malawi)

Only after World War II did the secret spill: Ōkunoshima, located in the Inland Sea of Japan between Hiroshima and Shikoku, was the top-secret site for manufacturing chemical warfare. When the factories were closed down, a number of exotic wild rabbits were seen freely roaming the island. They were assumed to have been the test subjects for the chemical weapons, which the military failed to eradicate when the factory was demolished.

A model waits to present a creation by Chinese designer Hu Sheguang for his collection show during China Fashion Week S/S 2016 in Beijing October 26, 2015. (Photo by Jason Lee/Reuters)