Arcade Fire's Win Butler plays impromptu gig with mariachi band before London gig – watch
The frontman welcomed concert-goers at The Roundhouse dressed in a skull mask
The frontman appeared in a skeleton mask to play 'Reflektor' – watch a video of the performance above.
Arcade Fire played their first UK show under the guise of The Reflektors, the pseudonym under which they've been performing gigs to promote their new album of the same name, on Monday (November 11) at The Roundhouse.
Arcade Fire's UK Return - 5 Things We Learned
Addressing the fact that the audience had, at fairly short notice, been told that "formal wear or fancy dress" was mandatory for the performance, Win Butler told the crowd: "To anyone who felt uncomfortable dressing up – I'm not sorry," said Butler. "At least 70 percent of you are getting laid tonight… As long as you showered. That's the secret. Boys."
Arcade Fire played another show at the venue the following night (November 12) and will later this week head up to Glasgow's Barrowland (November 15 and 16) before one night at Blackpool's Empress Ballroom (November 27).
Blog: Should bands ask fans to dress up at gigs?