The first, most literal, level involves a journey from the surface to the lowest depth zone of the ocean, with the album's movements getting progressively darker and more claustrophobic to mimic the diminishing light and increasing atmospheric pressure.

[2] Guitarist and songwriter Robin Staps described this aspect of Pelagial as a movement "towards the essence and origins of our desires, wishes, dreams, and all the fucked up attributes inside of our own inner selves that generate and shape them" and said that there are "a lot of Freud-like references" in the lyrics and song titles.

[2] Pelagial was written as a single piece of music in order to fit the concept of a journey through the depth zones of the ocean.

"[5] Subsequent to the band recording the instrumental album, it was announced that Rossetti had recently recovered from a disorder affecting his voice and would indeed contribute vocals to Pelagial.

[3] The limited edition version of Pelagial comes with a DVD movie made by Craig Murray, which Staps described as "basically a massive video clip.

[7] The movie, which will also be incorporated into the visuals for the band's live show, features a female protagonist who embodies the psychological aspects of the lyrics for Pelagial.

[7] Pelagial has received almost universal acclaim, with About.com describing it as "a stunning collection of ideas and emotions"[8] and Axis of Metal predicting that it would be a contender for album of the year in 2013.

[16][20] Scratch the Surface praised the band's decision to include both the vocal and instrumental versions of the album so as to offer both experiences to the audience.