Vocalist, keyboardist and songwriter Tony Kakko confirmed Sonata Arctica would start recording their ninth studio album in April 2016 in several home studios in Finland, with the main recording and mixing taking place at the Studio57 in Alaveteli, Finland. He also described the artwork of this new album, explaining:

Kakko says musical inspiration for the album came by opening his eyes and ears and letting everything in. The album title is inspired by The Ninth Hour described in the Bible, which is the moment when people are supposed to sacrifice and remorse according to that book.

The album opener and first single is "Closer to an Animal", a track that Kakko worked on two years before the album recording and which was brought around midway through the sessions. It has a reprise, titled "On the Faultline (Closure to an Animal)", which closes the regular edition of the album and marks keyboardist Henrik Klingenberg's first usage of an acoustic piano with the band. He mentions an influence of 80s music in his performance at the track.

"Life" was the first song in which the band worked on, but also the last to be finished, which made it the most altered song throughout the sessions. According to Kakko, "we had three different versions. I wasn't happy, the guys were totally excited by the first version and made it their own. But I thought it was pretty awful (laughs). I told them, 'We are putting it on hold.' I got back to it later and I think I got it right, edited some parts and changed things around".

"Fairytale" is a satire on the political events of the United States by the time of the album sessions. "We Are What We Are" was one of the few songs Kakko prepared as a demo for the band to listen to before the recording sessions. Unlike what he did for Pariah's Child, he did not record a demo for every song he wrote for The Ninth Hour. The song features Nightwish's Troy Donockley on Overton low whistle. Kakko showed it to him amidst their North American tour and suggested the guest performance.

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Wikipedia