Robots become after-dark tour guides at Tate Britain
19 August 2014 Last updated at 13:05 BST
Have you ever wondered what really happens when the lights go out in museums and art galleries?
Perhaps the exhibits come to life or swap places?
Well, last week children from around the world were given the opportunity to take a night time tour of one of Britain's most famous art galleries, the Tate Britain.
But showing them around were some very unusual night time helpers.