Teddy Sinclair — the artist formerly known as Natalia Kills, who is the artist formerly known as Verbalicious — is back with a new offering from her band Cruel Youth. Much like "Mr. Watson" before it, it's a moodier, jazzier affair than the singer-songwriter's previous polished pop leanings.

Like an Old Hollywood lullaby, "Diamond Days" twinkles with the nostalgic, bittersweet longing for better days gone by. Crooning to an old lover (or perhaps her old self), Sinclair sings, "You, you were just a fling / A beautiful addition to the valley of my vices," her honeyed rasp recalling the poetic brooding of Lana Del Rey, and perhaps the soulful contralto of the late Amy Winehouse.

The track's wistful, vintage synth-pop production (not unlike that of Marina and the Diamonds' Electra Heart ballad "Teen Idle") only serves to punctuate the artist's ache, making the song sound so familiar in its emotional poignancy. Listen below:

Formed last year with Willy Moon — Sinclair's husband, collaborator, and purported inspirer of doppelgangers — Cruel Youth is the two artists' "musical love child," according to an early press release. Describing the project as a "sanctuary," the singer also revealed that its formation was meant to be an escape from the "global witch hunt" she experienced after getting fired following her controversial X Factor New Zealand behavior in March 2015. Aside from releasing new music under Cruel Youth, she has also worked with Madonna and Rihanna since the incident, co-penning "Kiss It Better" off #ANTI.

The diamond days may be behind the artist once known as Natalia Kills, but with this release, Teddy Sinclair proves that the best is yet to come.

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