WARNING: The following contains major spoilers for the latest episode of Watchmen, "Little Fear of Lightning," which premiered Sunday on HBO.

HBO's Watchmen is beholden to the seminal comic book series, and even features such characters as Adrian Veidt, Laurie Blake and (somewhere on the periphery) Doctor Manhattan. However, viewers could be forgiven if they thought the television sequel would largely neglect the source material's memorable climax -- the attack by an "extradimensional alien" creature on New York City -- except for some vague references and, of course, the "squid showers" of the series premiere. They would be wrong, though. The fifth episode, "Little Fear of Lightning," rewinds to the world-altering events of Nov. 2, 1985, in a flashback that casts a key secondary character in a different light.

And, oh, yes, it gives us a building-size monster whose death unleashes a psychic shockwave that kills more than 3 million in the New York area.

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That includes Hoboken, New Jersey, where a young Wade Tillman, better known as Looking Glass, then a naive Jehovah's Witness missionary, newly arrived in the sinful city to spread the good word. Tricked by one of the sinners into accompanying her into a carnival funhouse, where she strips him naked and then flees with his clothes, Wade survives the attack, and bears witness to its devastating aftermath. Although he doesn't see the "squid," the viewers do, as the camera pulls back across the Hudson River and into Manhattan, the music shifting from a distorted "Careless Whisper" to a rousing "New York, New York."

It's a sight that Zack Snyder's otherwise-faithful 2009 adaptation didn't give audiences. However, HBO's Watchmen delivers, not only in showing the "alien" -- actually created in Veidt's lab as part of a plan to unite the Soviet Union and the United States against a common enemy, and saving the world from nuclear destruction -- but also in exploring the far-reaching ramifications of the tragic event, through the eyes of Wade Tillman.

Like other Tulsa, Oklahoma, police officers, Wade (Tim Blake Nelson), maintains a day job to disguise his secret identity, such that it is. Possessing an uncanny ability to detect when someone is lying, Wade makes a living spying on focus groups, and telling companies whether the participants are being truthful. Despite New York City's desperate attempts to boost tourism, 34 years after the attack, its marketing campaign isn't working, no matter what the focus group says.

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But the perspectives of ordinary Oklahomans are nowhere as interesting as that of Wade, a conspiracy theorist who lines his hat with aluminum foil, holds random, timed drills in preparation for another extradimensional attack, and leads a support group for those who suffer from "extra-dimensional anxiety" (they identity as "Friends of Nemo"). Wade's life, as bizarre as it may be, is turned upside down again after one such meeting, when he goes out for drinks with newcomer Renee (Paula Malcomson), whom he later suspects of being a member of the Seventh Kavalry, a violent white-supremacist group that embraces the philosophy, and imagery, of Rorschach.

Following Renee and her friend to a long-closed department store, Wade discovers Seventh Kavalry members conducting experiments with a basketball using teleportation technology. But it wasn't his instincts or fine detective skills that brought him there. The Seventh Kavalry had left him a trail of bread crumbs so that one of its members, U.S. Sen. Joe Keene Jr. (James Wolk) could present him with the truth: A classified video recorded in 1985 by Adrian Veidt (Jeremy Irons) intended to be watched in 1993 by newly inaugurated President Robert Redford, in which he proudly admits to being the architect of the "extradimensional monster" that materialized in Manhattan on 11/2, killing half the population and traumatizing untold millions more. "An elaborate, ridiculously engineered hoax," he calls it, "to save the world." He also acknowledges (again, this is in 1985) the need to maintain the peace with "additional, small-scale extradimensional events," which suggests the "squidfalls" experienced in the present day were put in motion by Veidt three decades earlier.

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It also means the highest levels of the U.S. government have played along with Veidt's elaborate hoax since at least 1993, to maintain civil order and, one would presume, world peace.

Although Sen. Keene views himself as setting Wade free with this information, asking only for a "squid pro quo" of ensuring Angela Abar (Regina King) is taken off the board long enough for the Seventh Kavalry to enact its mysterious plan. However, this surreptitiously copied tape has altered Wade's worldview as much as the sudden arrival by an "extradimensional" squid in Manhattan 34 years earlier. He's spent most of his adult life believing in other dimensions, racing to the safety of his underground bunker and wrapping his head in foil; it cost him a marriage, and who knows what else. Wade isn't free of the paranoia that's governed his life for the past three decades -- he's rudderless.

Perhaps that's why he informs on Angela, perhaps the closest thing he has to a friend, and acquiesces to Sen. Keene's request. However, as we see in the episode's closing moments, that may not be enough the the Seventh Kavalry.

Developed by Damon Lindelof, HBO's Watchmen stars Jeremy Irons, Regina King, Don Johnson, Tim Blake Nelson, Jean Smart, Louis Gossett Jr., Yahya Abdul-Mateen II, Tom Mison, James Wolk, Adelaide Clemens, Andrew Howard, Frances Fisher, Jacob Ming-Trent, Sara Vickers, Dylan Schombing, Lily Rose Smith and Adelynn Spoon. The series airs Sundays at 9 p.m. ET/PT.

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