From September 19 to October 4, 2022, filming took over the picturesque seaside town of Piran, Slovenia. Contracts with the town for lodging, blocked streets, and set-up for a cast and crew of 300 members were kept secret until a few days prior to arrival.
Ironically, in the United States, Mark Wahlberg is not allowed to possess an actual firearm in any manner due to a felony conviction for assault in an attack on a Vietnamese man in Boston in 1988.
In London the action takes place outside the theatre showing the musical Matilda. The action then goes inside the theatre but the song and scene the children are performing is not from Matilda musical. The song they are singing is "I Won't Grow Up" from Peter Pan.
Mark Wahlberg's character's first name is Mike and the last name of the alias he was given is Weston. Michael Westen is the name of the main character in Burn Notice: Operação Miami (2007) about a spy who doesn't work directly for the CIA, just like the agents in the Union.
Originally title called "Our Man from Jersey".