Many media outlets have speculated about Brendan Fraser's appearance in this movie, with many concerned about his health. The actual reason for Brendan Fraser's dramatic weight gain was that he had bulked up for his starring role in the the upcoming movie, The Whale, directed by Darren Aronofsky.
The noticeably-distorted shots throughout the film are the results of Steven Soderbergh placing wider Kowa Anamorphic lenses, which already have considerable barrel distortion on their own, on a large Vista Vision-sized digital sensor that's 1.5x the size of the format they were initially designed for, as he wanted to replicate the imperfect lens characteristics and look of the early anamorphic lenses from the era the film takes place in. In fact, the film has the unusual aspect ratio of 2.16:1 because it was initially planned to be framed in the more traditional 2.40:1 anamorphic ratio, but the barrel distortion on some of those shots ended up being so distracting that he re-framed the entire movie to the taller frame to make it less noticeable.
Sebastian Stan, John Cena, Nicolas Cage, and George Clooney were originally cast but were forced to drop out due to scheduling conflicts after the movie's shoot was delayed from spring 2020 to autumn 2020 due to the COVID-19 pandemic. Though it hasn't been disclosed which roles all of them were set to play, Steven Soderbergh has mentioned in interviews that Clooney was originally cast in the role eventually played by David Harbour.
During a July 2021 New York TImes interview with Dave Itzkoff, David Harbour (Matt Wertz) recounted the extensive COVID-19 protections that were instituted for the cast and crew during the autumn 2020 shoot for No Sudden Move: "We were in Detroit for two and a half, three months, sequestered in a hotel. But luckily it's Soderbergh. He did 'Contagion.' So all the C.D.C. guys that he worked with on that were there on set. We were talking about the vaccines. I would go to Soderbergh and be like, 'When is this going to be over?' And he would be like, 'Oh, sometime early next year, there'll be vaccines.' I was like, 'Which one?' He's like, 'Pfizer's doing very well - two shots.' It was incredible. You're making this movie and you're finding out what's actually happening at the C.D.C."
The restaurant Roma Cafe that is shown in the film , was and allegedly is a mafia hangout. The FBI had one of their largest exterior wire taps during the 1980's outside of the restaurant. They placed bugs in street lights and elsewhere. It led to arrests. Also the alleged boss held his coronation ceremony there in 2014