Starting in early December of last year, a series of videos started appearing on YouTube under the account amamiwhoami.
The videos, with titles like 18.104.22.1689321018 and Prelude 699130082.451322, start off innocuous enough.
They soon move on, though, to things like trees with arms, singing whales and birth imagery.
Nobody has said who's behind the videos. Goldfrapp seems like a possibility, since they've got a new album, Headfirst, on the way, and the imagery is very Goldfrapp-esque.
The one single that's leaked from Goldfrapp's album, Rocket, doesn't sound anything like the music in these videos.
Other artists whose names have been raised include Aphex Twin, Portishead and even Christina Aguilera.
Until amamiwhoami spills the beans, though, it is what it is.
If you've got ideas on who amamiwhoami is, leave a comment and let us know!