Factual error: The movie is set in October 1977, but Holland March is waiting in a line to fill his gas tank on an "even" day. The 'even/odd' rationing was instituted in California during the second oil crisis of 1979, in May. (00:06:30)
Factual error: We're in the year 1977, and it's established later by multiple elements that it's October 26th. However, at the gas station March reads a headline about a killer bee in Brazil (which is a plot point, even!), which refers to real life events from November of the same year. (00:06:45)
Factual error: Showing the exterior of Healy's apartment, it is established that he lives above the famous stand-up club "The Comedy Store." Showing the entrance though, they show also the board above it which is composed of signatures of famous comedians - most of them who never appeared on it in 1977, when the movie is set. For instance you can see Roseanne (Barr) 's signature on the bottom right corner, and also Pauly Shore's. (00:10:55)
Factual error: Holland and Jackson drive in 1977 from the protest to the next hint to Amelia's whereabouts, passing through the Chinatown Gateway Monument, which was built in 2001. (00:29:10)
Factual error: When Jackson and Holland are driving after leaving the burned down house, a billboard for Jaws 2 can be seen in the background, but the movie takes place in 1977 and Jaws 2 wasn't released until June 16, 1978. (00:32:55)
Factual error: March is already wasted at the party, and tells the barman that "it's the killer bees." In the background as he says those lines (and even better when the dancer gets on her knees) you can see a bottle with half its label torn. That's because you can still make out from the bottom (and the shape of the bottle) that it's a bottle of the premium variety of Beefeater gin, Beefeater 24, which was launched only in October 2008, a good three decades after the supposed year of the movie. (00:38:20)
Factual error: When Holland March is swimming behind the bar with mermaids, "Get Down On It" from Kool and The gang is playing. That song did not come out until 1981 and the film is set in 1977. (00:39:50)
Factual error: To show how March was plenty wrong in his deduction about airport traffic, a big plane flies above his head. The plane has the trademark modern South West bright blue livery, but in 1977 it would have the Desert Gold colors. Or no colors at all, since South West didn't serve Los Angeles until 1982. (01:07:20)
Factual error: The poster of Paul Simonon of The Clash in Holly's bedroom was neither captured nor made famous on the sleeve of 'London Calling' until 1979; the Nice Guys is set in 1977. (01:13:00)
Factual error: During the scene with Amelia in Holly's bedroom, on the wall you can see the iconic photo on the cover of the "London Calling" album by The Clash. It's a photo with the bassist smashing the guitar onstage at the Palladium September 20, 1979, almost two years after the movie supposedly takes place. But there's also a Blondie poster on the right of the bed which, while based in fact on a shot from 1976, is a modern cheap styling in pink leopard print widely, marketed on the internet today but that is not appropriate to the time period. (01:14:00)
Factual error: At the end they are drinking from a bottle of Captain Morgan's spiced rum. The movie is set in 1977, and Captain Morgan wasn't introduced to the US until 1984. (01:50:55)
Factual error: The movie takes place in 1977. A boy tells his father he is playing PacMan, which came out in 1980. Then we see a cabinet of Ms. Pacman, which came out in 1982.
Factual error: In the party scene Earth, Wind and Fire's song September is performed. The song was released November 18, 1978. The movie is set in 1977.
Factual error: The guys are walking down Sunset Bl and behind them is a liquor store with the phone number on the sign. The phone number begins with 323, an area code which came into being in the late 90s.
Factual error: The movie takes place in 1977. When the two leads arrive at the party, they are playing the Earth, Wind, and Fire song, "September" which was not even written until 1978. Also, just before they arrive, the soundtrack is playing "Boogie Wonderland," another Earth, Wind, and Fire song that also was not written until March 1978. (The band members at the party look like they are supposed to be Earth, Wind, and Fire themselves.) Later on, the soundtrack plays the Rupert Holmes song, "Escape (Pina Colada). That was not released until 1979.
Factual error: Near the end, there's a scene where they are sitting in their car, and behind them is a late 80's early 90's GMC van (black).
