Warning: Contains spoilers for Peaky Blinders season 6, episode 1.

In Peaky Blinders season 6, episode 1, the show breaks its long-running streak by not using Nick Cave and the Bad Seed’s “Red Right Hand” as the theme song, teasing the biggest Tommy Shelby change. Peaky Blinders season 6 will be the final season of the TV show before a Peaky Blinders movie completes Tommy Shelby’s storyline. While spin-off shows are expected set in the same universe, it seems unlikely that Tommy will return for them.

Since Peaky Blinders season 1, episode 1, Nick Cave and the Bad Seed’s “Red Right Hand” has appeared as the show’s theme song. It has also appeared as part of the score for Peaky Blinders at other dramatic and violent moments. As well as the Nick Cave version, the show has included cover renditions of “Red Right Hand” from Arctic Monkeys, Fidlar, Jarvis Cocker with Iggy Pop, and Laura Marling. “Red Right Hand” is such an ingrained part of Peaky Blinders that Nick Cave’s one-time partner, PJ Harvey, recorded a special cover specifically for the Peaky Blinders soundtrack.

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After being such a major part of Peaky Blinders for 5 seasons, the lack of “Red Right Hand” from Peaky Blinders season 6, episode 1, “Black Day,” stands out and makes a larger point. The themes of murder and violence in “Red Right Hand” has become a symbol of Tommy’s (Cillian Murphy) own violent nature and removing it marks how much of a changed man he truly is in Peaky Blinders season 6. When explaining to Michael (Finn Cole) why he doesn’t drink, Tommy says that it is just “fuel for the loud engines inside your head.” Those engines were the things that often drove Tommy to violence, and with Polly Gray (Helen McCrory) gone he has had less external checks on his violence and has had to find that control within himself, so it really shows how much Polly’s death has changed Tommy Shelby.

Tommy Shelby Peaky Blinders season 6 bodies

In an interview (via Deadline) creator Steven Knight noted that “Red Right Hand” would appear later on in Peaky Blinders season 6. However, executive producer Caryn Mandabach pointed out that the score is always from the point of view of Tommy and his perspective has changed since season 5. This suggests that the use of “Red Right Hand” later in Peaky Blinders season 6 will either be the result of Tommy Shelby backsliding into his violent ways or will be used to highlight a different aspect of him or another character.

The phrase “Red Right Hand” has meanings outside of the Nick Cave and the Bad Seeds song which make it a particularly appropriate song for Peaky Blinders. The phrase appears to be derived from John Milton’s epic poem Paradise Lost in which it refers to the right hand of God that metes out divine vengeance. Within Peaky Blinders, in season 2 Inspector Campbell (Sam Neill) hires a group called the Red Right Hand, an elite fighting force from the Ulster Volunteer Force, to kill Tommy Shelby (though they were obviously unsuccessful). In Peaky Blinders, “Red Right Hand” might be a sign of murder and vengeance, but it becomes clear that it won’t always be Tommy Shelby’s hand that the song refers to.

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Peaky Blinders releases new episodes Sunday on BBC.