Carrie Fisher became engaged to Dan Aykroyd during this shoot shortly after he saved her from choking, by applying the Heimlich maneuver.
John Belushi disappeared while filming one of the night scenes. Dan Aykroyd looked around and saw a single house with its lights on. He went to the house and was prepared to identify himself, the movie, and that they were looking for Belushi. Before he could, the homeowner looked at him, smiled and said, "You're here for John Belushi, aren't you?" The homeowner told them Belushi had entered their house, asked if he could have a glass of milk and a sandwich, and then crashed on their couch. Situations like that prompted Aykroyd to affectionately dub Belushi "America's Guest."
Some performers were not used to lip-syncing to pre-recorded songs, standard procedure for movie musicals. James Brown ended up singing his number live with a recorded backing (the rest of his choir was lip-syncing). John Lee Hooker's performance of "Boom Boom" was recorded live at Chicago's Maxwell Street Market. Aretha Franklin's performance is cut together from many, many takes, using the parts where her lip-syncing was actually in sync.
John Belushi was nicknamed "The Black Hole" because he went through hundreds of pairs of sunglasses during production. He would do a scene, and then lose the pair before filming the next one.
The following off-screen dollar amounts reflect inflation from 1979 (the year of production & principal photography) adjusted for 2022:
- Permission to film in downtown Chicago was given after John Belushi and Dan Aykroyd offered to donate $50,000 to charity after filming. This comes out to $178,684.15 in 2022 adjusted for inflation
- Producers rented the Dixie Square Mall in Harvey, Illinois, for the mall chase scenes. The mall had been closed for over a year. Rumors spread in the community that the mall was being refurbished, and would be reopened after filming was complete. Universal was later sued for over $87,000 ($310,910.42 in 2022 adjusted for inflation) for failure to "return the mall to its original condition", something that had never been agreed upon. After years of political wrangling, the Montgomery Ward anchor store and mall power plant were demolished, while the rest of the dead mall rotted. The rest of the mall was finally torn down and cleared away in 2012
- Universal had planned a gala Chicago premiere, but in May 1980, Universal president Ned Tanen said "Things threatened to get out of hand. Universal has decided instead to donate $50,000 ($178684.15 in 2022 adjusted for inflation) to charities, chiefly orphanages in Chicago." The film opened in Chicago at the Chicago Theater and 15 other Chicago-area theaters and drive-ins
- All the people in the concert were fans of the Blues Brothers. They had volunteered for a free concert, and were promised $100,000 cash. This comes out to $405,621.38
- When John Landis found out that film's budget was $17.5 million, he said, half-jokingly, "I think we've spent that much already." This comes out to $68,955,635.16
- At the time, it was one of the most expensive films ever made, costing $30 million. For comparison, Steven Spielberg's contemporary film 1941 (1979) cost $35 million ($141,967,484.16). It was even rumored that Landis and Spielberg engaged in a rivalry, the goal of which was to make the more expensive film. Its been suggested that it was amiable, since they were both friends at the time and have cameos in each others film. Coincidentally, both films feature Dan Aykroyd, John Belushi and John Candy. Unfortunately, Spielberg ended the friendship because of a fatal accident that occurred during filming Twilight Zone: The Movie (1983), even though John Landis was acquitted in court of criminal charges.
Frank Oz: Just before the Bluesmobile crashes through the Toys"R"Us, a man asks if they have a "Miss Piggy," while holding up a a stuffed Grover toy. This is a nod to Oz, the man who provides both Muppets' voices (a toy version of two more Muppets Oz also performed are visible in the same shot: Animal is sitting next to the counter and Cookie Monster is visible on a shelf in the background). The man with the toy is Gary McLarty, the Stunt Coordinator of this film, and of "National Lampoon's Animal House (1978)."
John Landis: The state trooper driving the second car, the one that shows up after the first car calls for backup, that chases the Bluesmobile through the shopping mall.