Anachronisms: The Dreams' success montage includes a picture of the trio standing on the Great Wall of China. The U.S. and China had no diplomatic relations from 1949 to 1971.
Audio/visual unsynchronized: The lip-sync is off during some verses of "It's All Over" and "And I Am Telling You I'm Not Going".
Continuity: While adjusting her outfit backstage during the Detroit Theater Talent show, Effie is shown adjusting her wig. In the very next shot, it is perfectly in place.
Anachronisms: During a 1965 press conference, a photographer uses a Nikon camera that was introduced in the late 1980s.
Anachronisms: When the 1962 Cadillac Deville Convertible is on the lift, it has all-weather radial tires, which didn't exist then, with treads that first appeared in the 1990s.
Factual errors: During the success montage, the Dreams' "Dreamgirls" single is shown climbing up Billboard magazine's "Top LP's" albums chart, not its "Hot 100" singles chart.
Anachronisms: In a scene set in 1965, the Dreams and Curtis are in the studio during the 12th Street riots in Detroit (according to the archival footage), which began on July 23, 1967.
Continuity: In the Dreams' version of "One Night Only", the girls' capes fall to the floor during the opening bars. After the next shot, they disappear.
Continuity: Just before the gospel break of the "Steppin' to the Bad Side" number, a medium shot of the Dreamettes features Deena on the left, Lorrell in the middle, and Effie on the right. The shot immediately following is a long shot showing the full stage, with Effie now on the left, Deena in the middle, and Lorrell on the right.
Incorrectly regarded as goofs: During "Steppin' to the Bad Side", tambourines appear just before the gospel break. It's part of the choreography, using an old stage and film musical technique.
Factual errors: When Effie goes to the welfare office, the American flag hanging on the back wall is backwards. The blue field should be in the upper-left corner.
Factual errors: In the montage, the entry in the charts does not make sense. The song is #1 in its first week, but it was also #8 the previous week.
Continuity: During the "It's All Over/And I'm Telling You" scene, Effie's wig is wider on the sides. In many close-up insert shots, the sides of her wig are tighter.
Errors in geography: During the "Steppin' to the Bad Side" montage, there is a flyover shot of the City of Chicago in which the NBC Tower is prominently displayed. The building was opened in 1989 - over 20 years after the time period the song was supposed to have been a hit.