Westworld is a futuristic show and demands your complete attention throughout. It follows a plot of the same name, but this is not like any other show. This park allows humans to live their fantasy—the answer to how is what you will find when you watch the show. The show is run by HBO, who had to pay attention to this show even more now without having a hit show like Game of Thrones to depend on.
Though the makers of the show have moved to Amazon to produce a different series, it is possible to say that Westworld will be renewed for a fourth and a fifth season even. But we cannot guarantee the fifth season right now as the makers have suggested that they will keep the show for another season and that might seem to be the last.
No official announcement is yet available about the release as season 3 of Westworld is still on the air. Once the series is off the television, we can hope for some official news about season 4, but whatever happens, it is most likely that the new season will not air before 2022. The show is highly complicated and futuristic and takes a lot of time for 18 episodes to be made in order to get a new season.
Regarding the cast, in Westworld, no character can be removed as the same person can come back as a host. Evan Rachel Wood will be back to play Dolores Abernathy along with other core characters.
New additions might also be made to the cast, but it is too soon to know any information as of now. The showrunners have stated that they have a rough idea as to which direction season 4 will go in, but nothing is much certain currently. With the war coming to an end, finally, we can expect Westworld season 4 to be full of big twists and turns!