Everything You Need to Know About Westworld

• How they behave: By design, everything the computerized “hosts” do and say is scripted—with just a splash of improvisation. They’re all just there to serve, and the park purges their memory at the end of every story. Hosts like the town saloon’s wise Madam (Thandie Newton) restart their “loop” following their predetermined storylines the next day, but guests can still disrupt these predetermined storylines depending on what they feel like doing. Each host is driven by something in particular, but their emotions are dialed up and down accordingly.

• What they believe: They don’t actually know they’re not real, and they think the guests there to do whatever they want with them are simply “new in town.”

• The rules: Hosts are incapable of killing guests, and guests are incapable of killing other guests. If a host takes a bullet from a guest, the park repairs them and they start over. When a host needs a tune-up, it can instantly come on and “offline” for a diagnostic at the Westworld version of the Apple Genius bar where they can chat with their makers to ensure they’re not plotting a massacre.

• Notable host: A glimmer of hope in this dark frontier: Dolores (Evan Rachel Wood) who has the sunniest outlook ever, even though she suffers extreme trauma on the daily. It’s why the creators feel erasing everyone’s memories is the least they can do.

• Popular attractions The real people, the “guests” who experience the luxury of Westworld’s delights, are all wealthy and their conduct makes everyone you’ve ever seen in a spring break movie look like a model citizen. In the world’s central spot, Sweetwater, there’s a saloon for prostitutes and gambling, and it’s flanked by the more mysterious badlands. Once in Westworld mode, tourists like the V.I.P. regular, the Man in Black (Ed Harris) and first-timer William (Jimmy Simpson) are encouraged to fulfill their deepest desires by engaging in any number of dubious new hobbies for the ultimate photo opportunity.

• How they behave: Nothing is off limits so most of the 1,400 visitors tend to follow their wilder impulses, treating the hosts like sex objects or gunslinging practice to blow off some steam. But they also come to find out who they could be, and if they want, they can live like a heroic cowboy “good guy” in a classic Western film.

• What they do: Because the hosts of this elaborate world don’t work alone, plenty of the story focuses on the creators who control the cast of characters. They must constantly track the hosts to ensure they’re obeying every command and sticking to the script. Fans of the classic movie based on Crichton’s book, Jurassic Park, will observe that the park’s omniscient founder, Dr. Robert Ford (Anthony Hopkins) is way darker than the guy who made the dinosaur playground as a “fun for the whole family” destination.

• The notable employees: There are several key people who make this wacky world work. We quickly learn the behavior engineers are mostly jaded about the artificial intelligence except for head of programming Bernard Lowe (Jeffrey Wright), who’s fascinated by their moments of consciousness, and hiding this in the least effective way possible. We also have Elsie Hughes (Shannon Woodward), a savvy coder; the arrogant guy masterminding the storylines, Lee Sizemore (Simon Quarterman); and no-nonsense Quality Assurance head Theresa Cullen (Sidse Babett Knudsen.)

The creatives have been operating from the same ambitious, reality-altering playbook for years, but small system error: everything’s going haywire. So they’re tasked with fixing a few of the robots who show signs of malfunctioning, questioning their realities and recovering traces of bad memories. The hosts appear to be evolving to gain consciousness, which would be a wrench in the park’s plan to continue using them as dispensable actors (and victims) in every guest’s fantasy.