David Bowie was a huge fan of Peaky Blinders. Bowie loved the show so much that he sent the production team a picture of himself wearing a razor blade-peaked flat cap. According to the Telegraph, the singer's "people" also made it clear to creator Steven Knight that he would love to feature on the soundtrack. At the scene where we see Tommy Shelby recovering from the injuries he sustained at the end of the last episode, we can listen to "Lazarus" by David Bowie whose song scored Tommy's woozy morphine-fuelled recovery.
The Faberge Egg depicted in this episode is the Lillies of the Valley. It was made in 1898 for Tsar Nicolas II and given to Empress Alexandra as a gift.
The song "Lazarus", by the show's big fan David Bowie, was added as a tribute, as the artist passed away on January 10th, earlier that year.
Cillian Murphy, Tom Hardy, and Alexander Siddig have all played Batman villains: Murphy played The Scarecrow in the Dark Knight Trilogy, Hardy played Bane in The Dark Knight Rises (2012), and Siddig played Ra's al Ghul on seasons 3 and 4 of Gotham (2017-18).