The assassin in the last scene is called "Venkman" - a reference to star Bill Murray's character in Ghost Busters (1984).
In a scene in the hotel, a character is shown watching Jon Amiel's earlier film, Copycat (1995).
After the interrogation scene in the hotel, Boris walks out of the room to call Dr. Ludmilla Kropotkin, and says: "Uri, get the rubber sheets... and watch that man." (pointing to Bill Murray's character). "Watch That Man" is the title of the novel on which the movie is based.
This was the first feature film to be made at Elstree Studios after the local council bought it from Brent Walker under a Compulsory Purchase Order.