A clock showing a countdown to the start of the London 2012 Olympics is unveiled on March 14, 2011 in London, England. The clock is starting five hours from midnight when 6.6 million tickets for the Olympics will become available and 500 days before the Games start. There is a six-week window to apply for tickets on the London 2012 website.

A man poses as “Lemongrab” from Adventure Time outside the MCM Comic Con at the Excel Centre in East London, October 25, 2014. (Photo by Andrew Winning/Reuters)

An actor plays an injured passer-by during Exercise Strong Tower, the scene of a mock terror attack at a disused underground station in central London, Britain June 30, 2015. London police held their biggest-ever terrorism drill on Tuesday, pitting the emergency services against a group of marauding attackers, nearly 10 years since four young British Islamists killed 52 people in suicide bombings on London's transport network in July 2005. (Photo by Peter Nicholls/Reuters)

Musician “Girli” poses for a portrait during London Fashion Week in London, Britain February 21, 2017. (Photo by Neil Hall/Reuters)

A model presents a creation from the Tom Ford Spring/Summer 2015 collection during London Fashion Week September 15, 2014. (Photo by Suzanne Plunkett/Reuters)

A model has her hair and make-up done backstage ahead of a show of British designer Jasper Conran at the London Fashion Week, in London, Britain, 15 September 2018. (Photo by Tolga Akmen/EPA/EFE)

Models present creations during the Pam Hogg catwalk show during London Fashion Week in London, Britain, September 13, 2019. (Photo by Henry Nicholls/Reuters)

An actress dressed as Black Cat poses for a photo at the London Super Comic Convention at the ExCeL Centre on February 23, 2013 in London, England. Enthusiasts at the Comic Convention are encouraged to wear a costume of their favourite comic character and flock to the ExCeL to gather all the latest news in the world of comics, manga, anime, film, cosplay, games and cult fiction. (Photo by Jordan Mansfield)