In the booklet to 2018's Vector, Haken offered these words of thanks to fans: "Keep spreading the virus." Virus, the band's eighth album, may share its title with the COVID-19 pandemic gripping the planet, but the album germinated during the writing sessions for Vector and were completed as a conceptual extension. Songs were penned and arranged on their tour bus after gigs with Devin Townsend. The concept here is set 20 years after Vector's open-ended conclusion, "A Cell Divides," created the need for a sequel to complete its labyrinthine narrative and character study that simultaneously involved everything from a catatonic protagonist to puzzle boxes to fallen empires.
The massive, machine gun-like staccato riff from a detuned eight-string guitar on "Prosthetic" has much in common with music by Meshuggah and Dream Theater. With its shifting rhythms, crash-and-burn verses, and hooky, harmonically expansive chorus and unhinged bridge, its challenging prog tropes and blastbeat drums offer delight. Single "Invasion" is introduced by singer Ross Jennings' complex melodic harmonies offered in polyrhythmic cadences as guitars, basses, and electronics prod him on. The tune travels effortlessly through prog and metal. While "Carousel" begins with a brief, poppy intro, it comes into aural view via immense keyboards, bass and guitar vamps, and drum flourishes that create tension between dynamic poles that are never resolved during its ten-minute duration. "Canary Yellow" harkens back to a younger Haken, with an eerie melody and pastoral keyboard passages; its complex rhythmic palette is the mature flowering of tenets showcased on Vector's "Veil." On the 17-minute, five-song suite "Messiah Complex," Haken travel all the way back to 2013's The Mountain to answer the question that has long flummoxed the band as well as fans: Who is "the Cockroach King"? and fills in the landscape by tying that revelation to Vector, too. There are many referents in the suite's five songs. "Ivory Tower" is a lushly melodic and harmonically complex jam that opens a doorway into the metallic heaviness and chaos that is realized in full on "A Glutton for Punishment," with its detuned riffing, maniacal blastbeats, and cascading keyboards. "The Sect" combines post-djent vamps with sweeping, knotty prog keyboards, then directly adopts Gentle Giant's trademark vocal counterpoint. "Only Stars" is a short, lilting ballad that reflects the travails and blessings of memory amid the conclusion of the narrative. Its nadir is framed by ghostly ambiences, strummed acoustic guitars, and muted pianos. Though different musically, Vector and Virus were meant to be heard in tandem, and while the earlier record provides context, Virus can be taken on its own as a challenging creative work that showcases the breadth and fullness of Haken's vision as commensurate with their ability to execute it flawlessly.