[2] The album's second single, "Puzzle Box", was released on 28 September 2018 for digital download, following the daily publication of six scrambled parts from it in the spirit of the song's theme.

He has a great reputation for the heavier end of our genre.Guitarist Charlie Griffiths added:[1] We've always had a heavy influence, but it was obvious from the riffs that were naturally coming out of us early in the writing process that this would be a more metal album.

These are some of the most riff driven songs we've ever written.Regarding the album's concept, Griffiths said: Musically it feels like a logical step from 'Affinity', but lyrically it's a bit more theatrical and about as 'rock opera' as Haken has ever got.

From there the story enters the point-of-view of the patient – who appears to be catatonic, but his mind is sparking with what could be memories, or delusions brought on by the treatment he's receiving – we leave this up to the listeners to decide [...] And that’s the challenge for the fans – to find out for themselves their own meaning for Vector as an album.When asked about the concept, keyboardist Diego Tejeida stated that the field of psychology was involved, as well as influences from psychoanalysis, Freudian theories, the Milgram experiments, Pavlovian conditioning, and operant conditioning experiments.

[6] Concluding the review for AllMusic, Thom Jurek wrote that "Haken's willingness to take chances keeps older fans in the fold because here, they've balanced a far more aggressive direction with more nuanced elements from each phase of their recorded development.