"THE National is not five dudes,” says Matt Berninger in a statement with I Am Easy To Find, his band’s eighth – and most extraordinary – album.

“That’s kind of been the core, but the truth is, very quickly with Boxer, Carin started writing,” he continues. “The doors have been wide open in terms of people coming in.”

Carin is Carin Besser, Berninger’s wife. That 2007 breakthrough record featured Fake Empire, an evocative track notably used in Barack Obama’s presidential campaign.

To the casual fan of their intimate epics, The National really are five dudes: multi-instrumentalists Aaron and Bryce Dessner, rhythm section Scott and Bryan Devendorf and frontman Berninger – brothers and schoolfriends who grew up in Cincinnati..

A long-term witness has been Graham MacIndoe, the New York-based Scottish photographer having documented them since their early days of playing small clubs in Brooklyn to the stadium shows of the Grammy-winning band they are today.

Bluntly put, they’re the American Radiohead: a seemingly insular band favoured by those alienated by the modern world.

Recent years have seen them refine their tobacco-stained, country-tinged indie rock with elements of electronics and a move towards wider soundscapes.

An example is the closing title track of 2017’s Sleep Well Beast, a hypnotic six-minute song with a flickering, dreamlike video by MacIndoe and artist Casey Reas. The album topped the charts in Canada, Ireland and the UK and went on to win the Grammy for Best Alternative Music Album in early 2018.

Sleep Well Beast was their Kid A, a game-changer which made it impossible to second-guess where they would go next.

Work on the follow-up began quickly following an approach to collaborate from Mike Mills – the director of Thumbsucker and 20th Century Women, not the REM bassist.

Berninger threw Mills a curve. The film director was offered full creative control over I Am Easy To Find, a project which became a 16-song album by The National and a 24-minute film by Mills starring Tomb Raider actress Alicia Vikander.

The album is not the film’s soundtrack, neither does the film depict the record in images.

Instead, Mills says, they are “playfully hostile siblings that love to steal from each other”.

Rather than narrative, I Am Easy To Find concerns itself more with intangibles: memory, emotion and what it means to be a person at a time where everything feels fragmented and, to borrow a lyric, there are “police in the museum”.

It’s not Berninger who sings that line, or perhaps even wrote it. Besser, a former fiction editor for The New Yorker, has significantly upped her lyric-writing here. And in I Am Easy To Find her husband’s lugubrious baritone is sidelined for a number of female vocalists such as Sharon Van Etten, Lisa Hannigan, This Is The Kit and Gail Ann Dorsey, a member of David Bowie’s band for 20 years.

If some fans were initially disappointed, they should stick with it.

I Am Easy To Find is a grower, says MacIndoe, whose relationship with the band goes beyond that of traditional photographer.

Coming Clean, his 2017 exhibition at the Scottish National Portrait Gallery, depicted a period of drug addiction and The National have supported his work in US galleries on themes of recovery.

“The music has evolved over the years and I like that – especially with the latest album,” MacIndoe says. “Though I’d been privy to some of the work on the new album from being in the studio with them over the previous years it took time to grow on me, but now I totally love and understand it.”