A woman dressed as the Star Trek character “Leeta” (C) and man dressed as “Rom” (2R) arrive to attend the “Destination Star Trek London” convention at the ExCeL centre on October 19, 2012 in London, England. The three-day convention, which opened to the general public today, will be attended by all five actors who played captains throughout the 46-year-old series. (Photo by Oli Scarff)

A policeman stands by a burning car, set alight during a communist march in the East End of London. (Photo by Topical Press Agency/Getty Images). Circa 1936

Labourers who work nearby nap on a road as cars drive past in Chongqing Municipality, July 23, 2013. (Photo by Reuters/Stringer)

In this Thursday, April 11, 2013 photo, an Afghan woman peers through the the eye slit of her burqa as she waits to try on a new burqa in shop in the old town of Kabul, Afghanistan. (Photo by Anja Niedringhaus/AP Photo)

An enthusiast dressed as a zombie takes part in the annual Zombie Walk festival in Prague June 1, 2013. (Photo by David W. Cerny/Reuters)

A Kenyan soldier takes cover as shots are fired in front of Garissa University in Garissa town, located near the border with Somalia, some 370km northeast of the capital Nairobi, Kenya, 02 April 2015. At least 15 people have been killed and some 60 were injured in an attack carried out by Somalia's Islamist militant group al-Shabab, according to local media reports. (Photo by Dai Kurokawa/EPA)

French artist Christophe Guinet, also known as “Mr Plant”, works on his plant shoe creation “Wood”, part of the artistic project “Just Grow It”, in his art gallery in Marseille, November 25, 2014. Guinet transforms name-brand Nike sneakers, cult footwear for urban youth, into vegetable compositions, creating a collection of artwork with trainers modified with tree bark, foam and flowers. (Photo by Jean-Paul Pelissier/Reuters)

A Sikh warrior, wearing a huge turban attends the annual fair of “Hola Mohalla” in Anandpur Sahib, in the northern Indian state of Punjab, Monday, March 17, 2014. Believers from various parts of northern India collect at the religious fair to celebrate the festival of Holi in a tradition set by the tenth Sikh guru Guru Gobind Singh in the seventeenth century. Nihangs, or Sikh warriors, display their martial skills and attire during the fair, believed to be maintained in the exact tradition as set by the Guru. (Photo by Altaf Qadri/AP Photo)