Listen: Sam Smith 'Spectre' theme song 'Writing's on the Wall' released

LONDON, Sept. 25 (UPI) -- English superstar Sam Smith's official theme song for the upcoming James Bond film Spectre was released online Friday, several weeks after its announcement.

The track, "Writing's on the Wall," is available for download and streaming on websites like iTunes and Spotify. Written with "Stay With Me" co-writer Jimmy Napes, the chilling tune carries Smith's unmistakable voice through character James Bond's deepest thoughts.

When breaking down the track with NPR's Morning Edition Friday morning, Smith says he tried to place himself in Bond's shoes as he wrote the song.

"My music is a diary and it's a recap of my life, and I wanted to bring that kind of honesty," he said. "In the lyrics -- 'How do I live, how do I breathe?/When you're not here I'm suffocating,' -- I wanted a touch of vulnerability from Bond, where you see into his heart a little bit."

The song follows such themes written and performed by stars like Adele and Paul McCartney in the past. "Writing's on the Wall," Smith says, was written in roughly 20 minutes. "It's the quickest song I've ever written," he told BBC's Radio 1 earlier this month. "I love the song so much."