The word “psychedelic” is one of those phrases – like “genius”, “edgy” and “Pete Doherty arrested” – which has become somewhat devalued by over-use. Yet it certainly suits this collaboration between The Shins frontman James Mercer and studio maverick Brian ‘Danger Mouse’ Burton – a short (barely 37 minutes), sweet’n’sour and head-spinningly trippy affair. Since first seizing our attention with The Grey Album in 2004 – an inspired, irreverent shotgun marriage of Jay-Z’s Black Album with The Beatles’ White Album – Danger Mouse has been the hardest working whiz kid in show business, collaborating with everyone from Gorillaz to Beck between holding down a day job as one half of Gnarls Barkley. You might imagine he was spreading himself a bit thin, but hooking up with Mercer seems to have unlocked new stores of creativity. Ears are pricked from the first bars of opener The High Road. Toytown melodica forms some delightfully incongruous icing on a sumptuous melodic layer cake, built on a bed of lilting acoustic guitar chords and then covered in warm creamy harmonies, finished with a lullaby sing-along. Mercer’s gently off-beam pop songs are lit up colourfully by the duo’s choice of arrangements. Vaporize lulls you into a sweet reverie with mariachi horns and hypnotic backing vocals, while the uneasy urgency of Mongrel Heart eases off into a giddy carousel of Wurlitzer-style organ. And just as you’re getting comfortable, the lyrical barbs appear: “Don’t laugh, we’ve been through this / If you want to f*** with me, you should know…” Your Head Is on Fire sounds like it has resurrected lost snippets from The Beach Boys’ Smile sessions, before waves of wah-wah-ing keyboards and whispering mantras softly lap at your ears. It’s intoxicating stuff. And the songs also hold up in different stylistic clothing: The Ghost Inside’s falsetto vocals, simple four-chord chorus and shimmying pop groove has echoes of unlikely bedfellows such as The Dandy Warhols. The vibe is a dreamy one throughout, but prickly undercurrents keep reappearing, as on Citizen when a disembodied voice sings: “This is a day without a trace of reason… the innocent are bound to the damned.” Rarely have such brooding sentiments sounded so alluring. In summary, then: we’ll have what they’re having.