Demons is a song by the US rock band Imagine Dragons. It’s from their first album Night Visions, released (发布) in 2012. The song’s video shows different people thinking about their hardships (苦难). And at the end of it, there is a fan of the band, Tyler Robinson, who is fighting against cancer. The song was also the theme song (主题曲) of the film Chronicles of the Ghostly Tribe (《九层妖塔》).