"Zipper Down", their fourth studio album, was released on 2 October 2015. The first single from the album "Complexity" was made available for streaming on Pitchfork Media's website. On 13 November 2015, the band was playing a sold-out concert to about 1,500 guests at Le Bataclan theatre in Paris, when the venue was attacked by terrorists, who killed at least 89 concertgoers. Following the attack, a Facebook campaign was created with the intention of getting the band's cover of the Duran Duran song "Save a Prayer" to number one on the UK Singles Chart. The campaign was promoted by Duran Duran, who promised to donate their proceeds from the sale to charity.