Love vinyl? Love art? Then you'll want to know about this.
700 artists and creatives from across the world have been asked to design a unique seven inch vinyl sleeve — the list includes Anish Kapoor, Bob and Roberta Smith, Gavin Turk and Paul Smith.
Inside each sleeve is one of seven tracks by a well known musical talent, ranging from John Lennon to Chvrches.
However, there's a catch. Nobody knows which artist has designed which sleeve (or which music track is inside) until they've been purchased.
All the singles are sold for £50 each and the money goes to charity — this year the charity is Amnesty International UK.
Records are sold on a first come, first served basis and queues can be lengthy — last year the longest wait was 36 hours.
If you're not in buying mode, all 700 will be on display in the four weeks leading up to the sale at the Sonos Studio in Shoreditch.
As part of the programme there will also be a panel discussion, a sleepover and a chance to record your own performance — see the full list of events for details.
Secret 7" is on display at Sonos Studios, Club Row from 8 April-1 May. The gallery will be open Tuesday-Sunday and is free entry. The sale takes place on bank holiday Monday 2 May.