Even the most ardent Pokémon fans probably thought the announcement of the Detective Pikachu movie was some kind of joke. After all, true fans are used to spending time reading up on strange Pokémon fan theories and binge-watching weird Pokémon anime way crazier than giving Pikachu a sleuth hat. Detective Pikachu is not only a pretty fantastic film, however: it's also a loving homage to Pokémon lore, stuffed to the sparkly cheeks with Easter eggs for fans.
And although the film is unexpectedly packed with scenes exuding humor, poignancy, and even surprisingly awesome CGI action, some of the coolest moments in Detective Pikachu are subtle nods to the series' winding history, which has somehow culminated in a story about an electric mouse trying to solve a mystery. And because Ryan Reynolds is involved, there are tons of little references to other niche elements of pop culture.
Howard Clifford's office is full of interesting trinkets, including a massive painting on one of the side walls. A big black circle on white canvas, it's actually a sacred Buddhist symbol called an Ensō.
By definition, an Ensō is ambiguous, but among its many possible definitions, one is the separation of soul and body - specifically so the soul can "use" the body for a creative purpose. That sounds a lot like Howard's plan to place his soul into a Pokémon so he can use the body for whatever he wants.
One of Pikachu's strangest quirks is his penchant for guzzling coffee. At one point in the film, Pikachu orders a coffee, saying he wants "another round, extra shot, blackest night." On the surface, that sounds like a very normal - if goofy sounding - order, but it may actually be a reference to the crossover Green Lantern comic Blackest Night.
The voice of Pikachu is Ryan Reynolds, who portrayed Green Lantern in the failed 2011 film of the same name. Could Reynolds be essentially mocking himself?
Those looking closely will notice several posters throughout Detective Pikachu referencing missing Pokémon. Many of them are found later in the film - during the underground fight.
It's never directly addressed, but it's implied that the Pokémon were taken from their original owners.
When Tim Goodman arrives in Ryme City, he stops by his father's old workplace, Ryme City Police Headquarters. While there, he meets with Hideo Yoshida, a Ryme City police lieutenant.
But when we look at Yoshiba's desk, his placard simply reads H. Yoshida. This could be a reference to legendary graphic designer Hironobu Yoshida, who has been helping design the look of Pokémon since Pokémon: Yellow.