While wiring Jesse for audio surveillance in the scene at the plaza, Hank instructs him, "Don't cross your arms, if you can help it." In Touch of Evil (1958), Charlton Heston as Vargas delivers a similar line, "Now remember, don't cross your arms," while wiring Sgt. Menzies to record Orson Welles' character Hank Quinlan.
The scene at the plaza resembles the scene at the beginning of The Conversation. Much of the surveillance equipment was purposely made to be like the surveillance equipment in the film.