Halfway through new album Apocalypse Bill Callahan intones "Everyone's allowed a past they don't care to mention". It makes sense, he has never been one to offer too much of his own life. Sure, the change from the Smog moniker to his real name seemed to usher in a more tender songwriter, and last album Sometimes I Wish We Were An Eagle was a beautiful record, yet contrast this with an album entitled Apocalypse; the title is an indication at what's to come. It's less accessible - sparser, darker, not as initially welcoming. However, it still bears all the hallmarks of what has made him such an enduring songwriter: the caustic wit, the trademark baritone and the ubiquitous equine references.

Callahan has talked about the distinction between "The Apocalypse" (the end of the world) and apocalypse (a revelation). This idea infuses the whole album. Apocalypse is a western, a journey revealed in two parts: both inward and outward looking; about the self and the world; dark and light; death and rebirth. It begins with opener 'Drover', Bill riding in, talking about the "wild, wild country", which "breaks a strong, strong mind".

It is the shuffling bounce of 'America!' which provides the album's most illuminating moment. Its proclamations of "I watch David Letterman in Australia" can seem caustically sarcastic, yet you realise that this is his love letter to the country, which he forgives, even after its past mistakes ('Afghanistan, Vietnam, Iran'). This yearning for his homeland is a side to his writing that he has never really revealed so explicitly before.

The shift in the second half of the album to the personal is signalled by the gentle and touching 'Universal Applicant' and 'Riding for the Feeling'. But they don't, and couldn't - prepare you for the closer, 'One Fine Morning', where all the elements of the album coalesce into a beautiful, shimmering whole.

A twinkling piano plays as he reflects on the vast plains and "The mountains bowed down / Like a ballet in the morning sun". It's one of the few times Bill has felt panoramic, riding off into the sunset, waiting for the sun to rise again, asking "When the earth turns cold and the earth turns black / Will I feel you riding on my back?".