Duh-da DUN DUN! Dadada DUN DUN! Dadada DUN DUH-DAN! DUN-DUH DADADA! Dun dadada! Dun dun dun!
- Every single frame of the film is full of Easter eggs for diehard fans to find — there was even a game on the official website to spot the Pokémon on the film poster!
The minigame was originally set around finding the references to the games on the teaser poster. - On the informational video about Ryme City on the train that Tim watches, Ryoma Takeuchi of Kamen Rider fame makes a cameo as a Pokémon trainer that looks a lot like Red.
- Once again, police in this universe rely on dog-type Pokémon, as seen with the beat cops walking with Growlithes and of course, Yoshida and his Snubbull.
- A Jigglypuff is shown holding the same sharpie/microphone that its anime counterpart is known to have, while also pouting next to some guy it seems to have made fall asleep with its singing, again just like its anime counterpart. This is hammered home by the fact that said Jigglypuff is voiced by Rachael Lillis, its original English VA. It also sings the same melody as in the anime.
- Pikachu tries to hop on Tim's shoulder just like Ash Ketchum's in the anime, but Tim refuses. He eventually warms up to it.
- Detective Pikachu has white fur on his belly, which has not been seen in Pikachu's design since early artwork◊ for Pokémon Red and Blue.
- The Turtles' "Happy Together", which was heavily featured in the first trailer, was used for Pikachu's first ever live action appearance: this ad for Super Smash Bros. 64. It's also a musical influence of the game series's theme.
- The parade balloons are based on the game designs for the Pokémon.
- In the food stalls scene, Detective Pikachu is standing in front of a bowl of leeks which look exactly like the variety held by Farfetch'd.
- In the second trailer, some of the music is similar to the beginning of the anime's first dub opening. An instrumental version of Gotta Catch 'Em All is playing early in the movie during their visit to CNM.
- The Greninja use swords made of water to attack, just like the Greninja in Super Smash Bros. for Nintendo 3DS and Wii U note .
- A Snorlax can be seen sleeping in the bike lane. Some things never change.
- A Genius Bonus example: Pikachu is a Deadpan Snarker who has an addiction to black coffee, a bitter drink. In the games, the nature of a Pokémon determines what flavors it likes and dislikes, and what's the preferred flavor of a Sassy Pokémon? Bitter.
- When Tim refuses to carry Pikachu on his shoulder, Pikachu says he's trying to achieve his step count anyway. The old tamagotchi-type Pokémon Pikachu toy required you to accumulate steps in order to feed your Pikachu. Similarly, the Pokéwalker made for Pokémon HeartGold and SoulSilver was a pedometer, which you could transfer Pokémon to, and encounter wild Pokémon and pick up items with. Pokémon GO also includes a pedometer element, with incubated eggs that hatch once you've walked far enough.
- Mewtwo is shown awakening in a tank, almost identical to the one where his anime counterpart was "born" in. In the movie, this is an Invoked Trope, since the villains recaptured the original Mewtwo since it "escaped" from Kanto 20 years prior. He even repeats his pre-breakout line of "they're outside".
- Mewtwo is captured by drones that torture him with electricity and prevent him from moving, like the ones in Pokémon: Mewtwo Returns.
- Aipom are the first Pokémon to cause problems for Tim and Detective Pikachu, just like in the video game.
- A Ditto unable to change its beady dot eyes despite its perfect imitations is reminiscent of Duplica's first Ditto. Although "Ms. Norman" is at least able to get the rest of the face right.
- Funnily enough Ditto only having Black Bead Eyes while disguised as Ms. Norman illustrates how Skintone Sclerae like Cilan's would look in real life.
- There's also Ms. Norman's name, which references Norman, the Normal-Type Gym Leader from Gen III and its remakes. This one can also double as some subtle foreshadowing.
- A big one for the main plot. People and Pokémon merging into a single entity? This has happened before. Bill's little accident with his teleporter resulted in a situation very similar to the Big Bad of this film's plan. Considering the direct callout to Mewtwo leaving Kanto 20 years ago, it might have directly inspired it.
- And then there is the spinoff manga Pokémon RéBURST, which plot centers around characters with the ability to merge with their Pokémon to do battle.
- The first half of the credits are filled with art of all the main characters looking like their art for the main series RPGs, including the humans, courtesy of Ken Sugimori, who did all the artwork for the Pokémon games. Also, during this sequence, an arrangement of the title theme from Pokémon Red and Blue is heard.
- Detective Pikachu (mournfully) sings the opening lines of 'Gotta Catch 'Em All', better known as the very first opening theme of the anime. The instrumental also appears when Howard and Roger are filming a promo for the parade.
- The name of Harry's hotel (according to the neon sign outside) is the "Oak".
- Lucy tries to catch the attention of a blond news reporter who wears a black suit with two gold bands around her waist. Her name is Cynthia McMaster.
- The Last Name Mcmaster is also shared by a character in the Detective Pikachu game
- For some viewers, this may not be the only time they've seen a Pikachu and a Mewtwo fight on top of Pokémon-shaped parade floats.
- One of the main plot points revolve around orange glowing headbands that allow a Pokémon and human to link minds, very similar to Pokkén Tournament.
- Pikachu refuses to use Volt Tackle in the cage match, saying it'll knock him out - a reference to how Volt Tackle delivers recoil damage to the user. Later in the film, when he uses it to knock Mewtwo through a building, he's visibly dazed and winded afterwards.
- When Tim quickly goes over the strategy for beating the Charizard, he lists Quick Attack, Discharge, Electro Ball, and Volt Tackle as the best moves Pikachu can use, who eschews them in favor of Thunder Bolt before realizing he's forgotten how. This is a reference to how Pokémon only know four moves and must forget one in order to learn a new move.
- Except for Discharge these are all moves that Ash's Pikachu has known in the anime, though he's never known all four at the same time (he replaced Volt Tackle with Electro Ball).
- When facing against the R-enraged Charizard, Pikachu tries kicking a Magikarp so it can evolve into Gyarados and wipe the floor with Charizard. This is similar to the anime episode "Pokémon Shipwreck", where James kicks a Magikarp, causing it to evolve into Gyarados.
- A little before that, Tim attempts to stop the rampaging Charizard by attacking the flame on the tail. As established in the anime and game, the more the fire diminishes, the weaker the Charmander evolution line, and Charizard by extension, gets. It's difficult to impossible to snuff it out like this (the flame continues to burn even when swamped by water), but its still an effective way to get a Charizard's attention.
- The first time we meet Lucy, she is wearing all pink with her hair up in a ponytail. Nurse Joy, a staple of the series, also is always in a pink uniform.
- Later on, when investigating the PCL, Lucy wears an outfit similar to the female trainer's default outfit from Pokémon GO.
- The drug is just named "R." The first evil organization was Team Rocket.
- The R Drug seems to be based on an ingame item called the Berserk Gene, left behind by Mewtwo near the collapsed Cerulean Cave in Pokémon Gold and Silver, and played a role in the original game that the film is based on. The effects of the item are even similar to the drug, boosting attack but causing confusion.
- There are Dialga, Palkia, and Arceus statues in Howard's office, similar to the statues that would have been in Eterna City in Pokémon Diamond and Pearl. It's a hint to which character is trying to play God.
- But wait, what happened to Giratina? Compare the position of Palkia and Dalgia to where they are when Giratina appears at the Spear Pillar in Platinum. In the center between the two... where Howard's desk currently is. Can you guess who the villain is yet?
- It's mentioned in the Pokédex entries for Torterra that people in ancient civilizations believed that there was a gargantuan Torterra under the Earth. This may likely be the inspiration for the lab deciding to use Torterra to experiment on increasing a Pokémon's size. And the fact that it worked implies that there might be some truth to those Pokédex entries.
- The four Pokémon who officially take part in the underground Pokémon cage match arena are Blastoise, Gengar, Charizard, and Pikachu. All four Pokémon are playable in Pokkén Tournament* , which has battles that function in the exact same way.
- Blastoise, Charizard, and Pikachu are also all Box Pokémon for the first generation of games in the US, and Gengar is the opponent's Pokémon in the original Red and Blue intro.
- Pokéballs are outlawed in Ryme City and Pokémon live among humans, but it's still common for all humans to have a partner Pokémon they live and work with, forming an empathic bond with them. This is not all dissimilar to how Pokémon Conquest worked, with "catching" Pokémon happening by bonding with them instead of using a Pokéball. It's also a light shout-out to the intro speeches most of the professors in the main games give, namely the first part about Pokémon being "Pets and friends".
- At first it appears that Mewtwo was responsible for running Harry's car off the road. Later on it's revealed that it was actually the Greninjas from the lab that did it, under Howard's orders. This is not the first time there has been a fake out involving these two. The same deception was pulled in a character reveal trailer for Super Smash Bros. for Nintendo 3DS and Wii U, initially setting up what appeared to be Mewtwo's silhouette, only to be revealed instead as Greninja.
- The phones everyone uses are shown to have buttons in a similar arrangement to the original Game Boy, which the original Pokémon games were released on. The device itself appears to be an evolution of the Game Boy design, which reflects the in-universe trend of the series' Pokédexes being based on the consoles they're played on.
- There's a news story in the movie about firemen working with Squirtles to put out fires. In Pokémon: The Series, Ash's Squirtle and the Squirtle Squad also worked with firemen to put out fires on at least three different occasions, including the episode where it was Put on a Bus.
- In addition, at the end of the movie, there is a shot of 4 Squirtles around a 5th one who wears a black robe that resembles the ones the Squirtle Squad wore.
- Among the products advertised on signs throughout Ryme City are Berry Juice, Poképuffs and Snap Cameras.
- The some of the first Pokémon we see are a group of Pidgey, Pidgeotto and Pidgeot flying over Leaventown, like in the opening scene of Pokémon HeartGold and SoulSilver.
- The Pokéball Tim uses to attempt to catch the Cubone works the same way it does in the anime— once the Pokémon is inside, it shakes and flashes yellow until either it fails, or the light turns green and the capture is confirmed.
- The remark from Tim which upsets the Cubone is that it likes wearing the skull of its dead relative. Insensitive though this may be, it's also accurate to several Pokédex entries which state that Cubone wears the skull of its deceased mother (e.g. Pokémon Yellow, Pokémon Silver and Crystal, or Pokémon FireRed).
- Pikachu loves when Lucy scratches him under his chin. Playing with a Pikachu in Pokémon-Amie or Pokémon Refresh shows that this is a favorite spot for all of his kind.
- Tim follows his friend, Jack, to catch a Pokémon, unaware that Jack is setting him up to catch it. Where do they find this wild Pokémon? In the tall grass.
- May be unintentional, but one of the default names for Red in the original was "Jack". He's even dressed up like a Pokémon Trainer, and is talking about leaving town.
- Ever since breeding was introduced to the Pokémon games, the majority of players got into the habit using Ditto to breed with their other Pokémon by using its Transform ability to become a compatible mate. The Ditto that Tim has to fight transforms into Lucy and he admits that he's attracted to the real one.
- There are nods to unofficial material too: the underground arena fight scene between Detective Pikachu and a Charizard looks like it was lifted from Pokémon Apokélypse, a Darker and Edgier reimagining of the Pokémon world that prominently featured a fight to the death between those two same Pokémon.
- The end credits open with a recreation of the classic black-and-white battle screen from Pokémon Red and Blue (pictured above), before transitioning to the more vibrantly-colored manga art by Ken Sugimori.
- Some people were confused by Pikachu finding solid shuriken-like objects at the scene of Harry's crash from the Greninjas' Water Shurikens. But remember that Water Shuriken is a Physical Water-type move, not a Special move, so it makes perfect sense seeing as Greninja throws shurikens coated with waternote .
