As Radiohead disciples would agree, much of the pleasure (and for detractors, the torture) of following the English band is unearthing its 10,000 Easter eggs, including obscurities that pop up over the decades.

One such track is True Love Waits, an acoustic dirge espied on I Might Be Wrong: Live Recordings in 2001, and which was finally released as a spectral piano ballad on the band's ninth studio album, A Moon Shaped Pool, in 2016.

And now, another elusive one - Dawn Chorus - has resurfaced, this time on frontman Thom Yorke's third solo album, Anima.

The song was brought up in a 2009 interview where it was described by Yorke as his favourite song for Radiohead. It was teased over the years, most recently with its title registered in 2016 as the name of a company titled Dawn Chorus LLP, in the build-up to the release of A Moon Shaped Pool. But it eventually ended up on Yorke's solo album.

Here, on Anima, Dawn Chorus is the fourth out of nine tracks, and arguably the album's emotional fulcrum. A slo-mo lament about love, melancholia and regret, it soundtracks the closing scenes of a short musical film, also called Anima, directed by Paul Thomas Anderson and available on Netflix.

Yorke and real-life partner, Italian actress Dajana Roncione, are seen spinning around, awakening in the shadowy alleys of France's Les Baux-de-Provence as the sun rises over a synth of sparse, sustained keys. Drained, he intones: "If you could do it all again/Yeah, without a second thought/I don't like leaving/The door shut."

The song provides unusual respite, an afterglow of equanimity in an otherwise dystopian landscape. You can feel the release. Subscribing to Carl Jung's theories of the unconsciousness - anima being the "inner feminine of the male personality" - Yorke hearkens for connection amid the desperation.

To that end, he is adept at pinpointing subterranean impulses which fuel urban anxiety, the purgatorial state between sleep and sleeplessness.

"Show me the money/Party with a rich zombie/Suck it in through a straw," he wheezes through Traffic, a jittery nightmare studded with cryptic Morse-code blips and escalating synthesizer hums.

The Orwellian menace is compounded by the scary spectre of "humans the size of rats" in Last I Heard (…He Was Circling The Drain). Keyboard chords grow and cave in, like a cancerous growth. The refrain - "I woke up with a feeling that I just could not take" - whirrs around, as if one is truly trapped.

Long-time Radiohead producer Nigel Godrich splices the digital F/X with Yorke's own unearthly voice, sometimes an eerie, beseeching keening, and other times, a supposed sane voice of reason.

The latter he adopts for The Axe, a Black Mirror-ish number where the line between humanity and artificial intelligence is erased.

"G******ed machinery/Why don't you speak to me? One day I'm gonna take an axe to you," he promises, surrounded by wave after synth wave and an unrelenting march of goose-stepping handclaps. "I thought we had a deal," he repeats, caught between dream and blinding reality.