Pokémon the Movie 20: I Choose You! Was officially revealed during the broadcast of TV Tokyo's Oha Suta program, revealing a teaser trailer and poster of the anime. The film was released in Japan on July 15, 2017 and has a full cast of Japanese voice actors. The film topped Japanese box office records, earning first place and in the first two days had grossed more than 516 million yen (£3.53 million, US$4.61 million).
It's a Japanese anime adventure film produced by Japanese studio OLM, Inc and was premiered at Japan Expo in France on July 6, 2017. The teaser trailer shows Ash Ketchum, Pikachu and the Legendary Pokémon Ho-Oh, with only six people in the cast list we know the movie will not feature Ash’s common companions Misty or Brock which has received a lot of fan criticism on social media saying "It's almost like Brock and Misty never existed."
The movie will centre more around Ash and Pikachu while developing their relationship more so than the original anime did in the first season and also feature some new Pokémon from Sun and Moon like Incineroar and Lycanroc. It has also been confirmed that Ho-Oh will be an important character to the storyline.
This is the twentieth Pokémon movie and is a retelling of the Indigo League anime series to commemorate the anime's 20th anniversary and also explore some original scenes in more depth that weren't developed on very much in the series, like when Ash first receives Pikachu from Professor Oak. The movie title is also a reference to the first episode of the anime and as you can see in the trailer there are scenes from the first episode that have been remade.
Pokémon the Movie 20: I Choose You! Trailer (English Sub)
There hasn't been an official release date for anywhere outside of Japan but U.K and American fans are requesting that voice-actress Veronica Taylor reprises her role as the English voice of Ash Ketchum and also for the film to be released in theatres.