10 Sci-Fi Hard Rock Albums You Need To Hear

9. Crack The Skye - Mastodon

Possibly the most "out there" storyline to accompany an album on this list, Mastodon's Crack the Skye is a mind-expanding, space-crossing tale of a disabled child's spirit eventually being trapped inside Rasputin, only to break free and - as the title says - crack the sky.

Brilliantly, it doubles as a metaphor/tribute to drummer Brann Dailer's sister, hence the "misspelling" of Skye in the name.

Music-wise it's more of that Mastodon stomp and heft we've grown to love. Crack the Skye was the band's fourth album, and having laid down massive tree-fellers like Blood & Thunder and ALL of Blood Mountain, Crack the Skye afforded them the space to experiment.

Penning the tale of a lost soul visiting cults and the devil, being part of religious ceremonies, getting trapped and finally being free is one hell of a story, with a surprisingly touching payoff. It makes for one of Mastodon's bravest works.