Demon Days is the second studio album by British virtual band Gorillaz, released in May 2005. A groundbreaking fusion of rock, hip-hop, electronic, and pop, the album features an impressive roster of collaborators including De La Soul, Neneh Cherry, Martina Topley-Bird, Roots Manuva, MF DOOM, Ike Turner, Bootie Brown of the Pharcyde, Shaun Ryder, Dennis Hopper, the London Community Gospel Choir, and the Children's Choir of San Fernandez. The album includes hit singles such as "Feel Good Inc.", "Dare", "Dirty Harry", and "Kids with Guns".

Demon Days debuted at #1 on the UK charts and #6 on the US charts, surpassing the success of the band's self-titled debut. With over six million copies sold worldwide, it stands as one of the most critically acclaimed and commercially successful albums of the 2000s.