The scenes in the vampire nightclub were filmed in the Dublin tourist attraction "Bram Stoker's Castle Dracula", which has since closed.
In a 2022 interview with Behind the Lens Online, Conor McMahon explained how the process of casting a short promo for the film led to a major change in the initial script: "In the casting of that, I found my vampire actor, but I couldn't find anyone to play off him. Like I was casting all these other mid-20s actors because I was looking for a best friend, and, just by chance, some wires got crossed and this young guy, Karl Rice, who was like 15 or 14 at the time, came in to read and I was like, 'Oh well, he's the wrong age, but I don't want to send him away' and I just brought him in. And it was just, in the minute I saw the two of them acting together, there was something about a younger teenager saying the lines and talking about vampires... There was suddenly this other layer to it. Then the idea came to me when I saw the two of them, 'Oh my God they have to be brothers' because if the stakes were high before, you know if you're gonna stake a friend, but what about a family member? That's a much harder dilemma... So I went home after that casting and I rewrote the whole script."
This is not the first time Anthony Head has acted as a mentor teaching people to fight vampires. One of his most famous roles was as Rupert Giles, Buffy's "Watcher," in Buffy - Im Bann der Dämonen (1997).