Phil and Paul Hartnoll sound like they’re getting their second wind. Having released a 30th anniversary collection last year, the brothers have hit a rich vein of creativity.

Sketched out during lockdown and recorded in the wake of the worst of the pandemic, the shadow of Covid looms large over Optical Delusion, from the haunting ‘Day One’, through the soaring ‘The New Abnormal’ to the electro-elegiac ‘Requiem For The Pre Apocalypse’.

‘Ringa Ringa (The Old Pandemic Folk Song)’ begins life as a glowsticks-aloft banger, before the Mediaeval Baebes’ haunting ‘Ring O’Roses’ – the nursery rhyme whose origins are widely attributed to the Black Death – ghosts in from stage-left.

Lead single ‘Dirty Rat’ features the vocal talents of Sleaford Mods’ Jason Williamson. It’s a magnificent techno-rant at the Daily Mail-reading voters who spend their lives “blaming everyone who doesn’t look like a fried animal”; the accompanying video has already racked up over half-a-million views.

Elsewhere, we veer from the disquiet of ‘You Are The Frequency’ and the glitchy claustrophobia of ‘Home’ – which boasts the vocal talents of London singer-songwriter Anna B Savage – to the tinkling loveliness of ‘Are You Alive?’.

The latter features eight minutes of quietly insistent rhythms and delicious vocals from sibling duo Lily and Jack Wolter, aka Penelope Isles. This is as fresh and vibrant as the Hartnoll brothers have ever sounded, over a remarkably productive career.

8/10