Late night openings at museums and galleries are now a firmly established part of London's cultural scene.
The Science Museum's monthly shindig remains one of the best and most popular.
Experts showcase some of the latest technology and talk about topics like climate change, space exploration and forensic science.
Diverse make-your-own activities take place, which in the past have included building a volcano or a motorised Dalek.
Tonight's Late is themed around the future, looking ahead to what we might expect from science, engineering and technology.
Sideshows include the prophecies of the Jetsons, a molecular gastronomy workshop, a (pretend) pregnant man and, somewhat contra-theme, a recreation of sounds from the Great Exhibition of 1851.
Queues can stretch round the block close to opening time.
Simply turn up, walk in for free, grab a glass of wine and enjoy the world-beating displays and live entertainment without the normal ruckus of children running about.
The tour, led by an experienced guide, travels to three specially chosen events and exhibitions, beginning and ending at Whitechapel Gallery.
Some of the regular crowd-pleasers are the pub quiz, comedy show, silent disco and speed dating.