Crack the Skye

Crack the Skye is Mastodon's fourth studio album, following Remission, Leviathan and Blood Mountain. It came out in March 2009 and is a concept album, its story blending science fiction with Tsarist Russian history. Underneath that sits real hardship: the album is named after drummer Brann Dailor's late sister Skye, and it also reflects guitarist Brent Hinds' recovery from a brain hemorrhage suffered in a fight after the 2007 MTV VMAs.

It's also the record where Dailor steps up as Mastodon's third lead vocalist, and he wrote most of the lyrics while Hinds wrote most of the music. That split gives the album its character, with progressive metal ambition carrying very personal material. It debuted at number 11 on the Billboard 200 with 41,000 copies sold in its first week, and had reached 200,000 in the US by September 2010, making it one of the band's best sellers.