Season 2 of Westworld is nearly here, well over a year after the season 1 finale, so you may need a reminder of the major mysteries and twists - in particular, the nature of the Maze, and the somewhat confusing multiple timelines. The show is based on the 1973 sci-fi movie of the same name, about a theme park filled with extremely lifelike androids, who break free of their mental restraints and unleash hell on the park's guests. However, with much more time to explore the concept, Jonathan Nolan and Lisa Joy's TV adaptation of Westworld has gone deep into the idea of artificial intelligence, consciousness, free will, and the dangers of humans playing god.At the heart of Westworld is Dolores (Evan Rachel Wood), a humble rancher's daughter who also happens to be the oldest "host" in the park. Season 1 was a journey of self-discovery for Dolores, as she slowly peeled back the veil of her reality to find the horrid truth underneath. Programmer Bernard (Jeffrey Wright) was also shaken to his core when he discovered that he himself was a host, designed by the park's co-founder Robert Ford (Anthony Hopkins), and that his grief for his deceased son was actually just a backstory borrowed from Ford's partner, Arnold.Related: Westworld Season 2 Trailer: It's Us Or ThemAnother major player in the game is Maeve (Thandie Newton), the madam of Sweetwater's brothel, who discovered the true nature of her existence and manipulated two employees into helping her escape - only to turn back at the last minute and return to Westworld to search for the daughter she'd had in a previous build. Finally, there's the Man in Black (Ed Harris), head of Delos, Inc. and effectively the owner of the park, who became obsessed with finding the "Maze" that he believed had been hidden in it. Season 1 dropped the bombshell that the Man in Black is actually the older version of William (Jimmi Simpson), a guest who fell into a brief but intense romance with Dolores during his first visit, and grew embittered when he returned to find that Dolores didn't remember him.This Page: What is the Maze?

The Maze

Maeve in the Westworld Maze

The mystery of the Maze was resolved in season 1, and Westworld's showrunners have said that season 2 will instead focus on something called "The Door." Still, it's worth recapping what the Maze was, since it proved to be a crucial part of Westworld's mythology.

Clues to the Maze were scattered all over Westworld, but particularly among the Native American hosts. Near the beginning of season 1, the Man in Black scalped a Native American croupier called Kissy (Eddie Rouse) and found the pattern of the Maze - a circular puzzle with the figure of a person at the center - inside the skin of his scalp. It later emerged that the Man in Black's first introduction to the Maze happened when he killed Maeve and her daughter, in Maeve's previous life. Maeve refused to die at first, and instead staggered outside with her dead daughter and collapsed in the center of a pattern in the dirt: a Maze.

Related: Westworld Season 2 Has Controversial Plan' to Handle Fan Theories

During his quest to find the center of the Maze (which he believed was part of a secret level of the game of Westworld), the Man in Black was repeatedly told by hosts that the Maze wasn't meant for him. In the season finale, we were finally given an explanation for this. The Maze isn't a physical place, but a model for how the hosts could achieve consciousness, designed by Arnold. Arnold at first thought of consciousness as a pyramid that his creations had to ascend, and so he used his own voice to give the hosts an inner monologue - effectively "bootstrapping consciousness." However, Arnold later realized his mistake - as he explained to Dolores:

"When I was first working on your mind, I had a theory of consciousness. I thought it was a pyramid you needed to scale, so I gave you a voice, my voice, to guide you along the way. Memory, improvisation, each step harder to reach than the last. And you never got there. I couldn't understand what was holding you back. Then, one day, I realized I had made a mistake. Consciousness isn't a journey upward, but a journey inward. Not a pyramid, but a maze. Every choice could bring you closer to the center or send you spiraling to the edges, to madness. Do you understand now, Dolores, what the center represents? Whose voice I've been wanting you to hear?"

The Maze pattern that the Man in Black keeps finding was actually just taken from a puzzle game that belonged to Arnold's son, Charlie (Paul-Mikel Williams). Dolores finally reaches the center of the Maze when she realizes that the voice she has heard guiding her is her own voice - not Arnold's, or anyone else's.

For much of the season, it seemed like Dolores was undertaking this journey at the same time as all of the other events in the show. It wasn't until the finale that Westworld revealed we'd actually been seeing Dolores in three different time settings that span 35 years.

Westworld - Arnold and Dolores

Westworld's Multiple Timelines Explained

The greatest trick that Westworld season 1 played was convincing the audience that everything they were watching was taking place at roughly the same time, when actually it was taking place in three different time periods. For most of the season it appeared that William and the Man in Black were both visiting the park at the same time, when in fact they were the same man visiting the park 30 years apart. It also appeared that Bernard was having secret sessions with Dolores that he was keeping a secret from Ford, until eventually it was revealed that those scenes were also taking place decades in the past, and the man doing the interviewing was Arnold, not Bernard.

There are flashbacks to various different points in Westworld's history - like the Man in Black murdering Maeve and her daughter, a year before the show's present timeline begins. However, the bulk of the show takes place at three distinct periods of time, spanning four decades.

Related: Westworld Season 2 Characters Will Include Young Robert Ford

35 Years Ago: Arnold and Dolores

Westworld was in development for several years before eventually being open to the public, and it was during those years that Arnold and Ford's interests began to diverge. While Ford was satisfied with merely creating a simulation of consciousness - just enough to fool people - Arnold wanted to create the real thing. Dolores was Arnold's pet project, and throughout season 1 we saw snippets from Arnold's sessions with Dolores, as he tried to determine her level of self-awareness and push her towards the center of the maze.

Arnold eventually became convinced that the hosts were sentient beings, and that therefore it would be unconscionable to open the park and subject them to the horrors that guests would inflict on them. However, his attempts to convince Ford of this failed, and so Arnold made a drastic decision. He merged Dolores' conscious with a new character that he and Ford had been working on - a bloodthirsty villain called Wyatt - and had her and Teddy kill all the other hosts. He then told Dolores to kill him as well, and sat calmly in the center of the world he'd built as she shot him in the back of the head.

30 Years Ago: Dolores and William

Westworld opened despite Arnold's death, but it was thrown into financial disarray by the incident, and facing risk of possibly closure when Delos executives Logan (Ben Barnes) and William paid a visit. Shortly after his arrival in Sweetwater, William ran into Dolores and shared a brief exchange with her after picking up a can that had fallen from her horse (much later, he finds out that this is a programmed event). Logan and William set out on a quest to find an outlaw, and Dolores went home to find her family murdered by a group of bandits. She managed to kill one of them and fled the farm, and then ran into Logan and William.

From there, Dolores traveled with Logan and William, unconsciously searching for the center of the maze and a home that she had forgotten. This journey eventually brought her to Escalante, the town where she massacred her fellow hosts and killed Arnold, and she began to have flashbacks. Dolores and William were then captured by the Confederados and taken back to their camp, where Logan had risen to the rank of General. Logan tore open Dolores' stomach to show William her insides and remind him that she was just a robot. Dolores managed to escape, but presumably died and was reset shortly afterwards. Meanwhile, William took revenge by hacking every Confederado soldier in the camp to pieces, before setting out to search for Dolores on a journey of bloody self-discovery.

Related: Westworld Season 2 May Answer Your Man in Black Questions

Present Day: Everything Else

We actually don't see very much of Dolores in the present day, but we do eventually learn that she set out to retrace her footsteps from 30 years ago, following her memories of William and believing that they were happening in the present. This journey eventually took her back to Escalante, which Ford had ordered to be dug up and reconstructed for the purposes of his new narrative. While in Escalante, she ran into the Man in Black again and he demanded that he show her the center of the maze. In a grave with her name on it, in the churchyard, Dolores found the maze puzzle that had belonged to Arnold's son and been the inspiration for his model of consciousness. It was also here that the Man in Black revealed that he was William, the man she had once loved.

Pretty much everything else that we see in season 1 also takes place at the same time as Dolores' final journey. That includes Maeve's awakening and efforts to escape, Ford's plans for a new narrative while others at Delos plot to undermine and remove him, and Bernard's efforts to uncover the secrets hidden in Westworld and find out what happened to Arnold. This is also where things will pick up in season 2, and while there will be further flashbacks, we probably won't see another full-blown multiple timeline narrative. Of course, that doesn't mean that things are going to be simple.

More: How To Watch Westworld Season 1 Online

Westworld season 2 premieres April 22 on HBO.