After the bright and breezy "A Sound is a Memory", and the mellow, restful "Family Album", "Aliens" is a return to the darker, experimental sounds of the debut album.
Many of the tracks on this album forgo traditional structure but like the tracks on "The Sounds of Geisha", the rhythms are formed by the music and instruments rather than relying on beats. Low frequency drums are present on Wanton, Alien Alien, and Form, for example (with Gold featuring particularly nasty distorted beats), while tracks like Return, Form, and Vacuum track their progress through a more ambient approach.
While not overtly musical, these tracks do have melodies scattered throughout, and as the album concludes we have flashes of beauty through the darkness - Alien Alien is the most melodic piece of music on this album and represents a high point.
Three bonus tracks are also included on this album.