Time Out says
Get your lungs ready to belt out some serious seasonal cheer at this enormous Christmas singalong organised by the people behind The Sunday Assembly. The house band and choir from the non-religious gatherings will lead a line up of December-only classics such as 'Merry Christmas Everyone', 'I Wish it Could Be Christmas Everyday' and East 17's 'Stay'. Guests are promised some special guest appearances but warned that huge quantities of good cheer are obligatory. Mulled wine will be on sale and you're likely to regret any outfit that doesn't involve a Christmas jumper. Booking recommended via the event page.