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

The latest episode of Watchmen took viewers back to the day of Adrian Veidt's gruesome manufactured alien octopus invasion and showed us the effect it had on survivor Wade Tillman, who would become the masked officer Looking Glass. But while "Little Fear of Lightning" showed us how Wade had built his alter ego persona around the event, it also took a bit of time to further advance the mystery at the center of the season: the murder of Judd Crawford, and Will Reeves' connection to the Chief of Police Judd Crawford's death.

After Angela Abar discovered Will Reeves was the grandfather she had never met, he disappeared from her grasp, taken back to the protection of the mysterious trillionaire Lady Trieu. The only thing he left behind for Angela was the bottle of pills that he's been ingesting ever since she met him. Now, thanks to some help from Wade and his ex-girlfriend, we finally know what the pills Will Reeves is taking are.

The pharmaceutical drug is called Nostalgia, and it allows those who take them from reliving old memories. But if the name sounds familiar to Watchmen fans, it's because Nostalgia featured prominently in Alan Moore and Dave Gibbons' original comic... as a perfume.

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Watchmen TV Nostalgia

While the Nostalgia perfume never played any central role in the Watchmen comic, it was ingrained in its universe. The cosmetic was created by Adrian Veidt's company, and it was advertised on billboards, newspapers and the like. The world of Watchmen was rich and finely detailed, and the Nostalgia perfume was an important part of that immersion. Now, the HBO television series not only works the brand into its latest episode, but it also shows the unexpected product it has now become.

The "Peteypedia Files," which are published on HBO's website and work as official, in-universe backmatter documents to the episodes, reveal the Nostalgia pills are manufactured by Trieu Industries, Lady Trieu's company. As we learned in "If You Don't Like My Story, Write Your Own," Trieu bought Adrian Veidt's company and turned it into a trillion-dollar vehicle. Therefore, we can deduce that after absorbing Veidt Industries, Trieu took the popular Nostalgia brand to create a new product that delivers exactly on the promise of its name -- just like the perfume, but also incredibly differently.

As described by the Peteypedia Files, "NOSTALGIA by TRIEU is a revolutionary, all-natural, personally customized medication for people suffering from anxiety, dementia, and psychic trauma."

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What's more, the episode even works in another reference to the Nostalgia perfume. In fact, "Little Fear of Lightning" takes us to Wade Tillman's day job, where new products are tested on focus groups. One of these products is the Mercy perfume, whose bottle is clearly meant to resemble Nostalgia from the comics.

While the Nostalgia drug is meant to treat people, it may also provide answers. Now that Angela Abar has ingested all of her grandfather's pills, she may not only experience some difficult side effects that blur the edges between her and her grandfather in her mind. However, that ensuing hallucinogenic experience may also show her the truth about Will Reeves, her family and maybe even herself.

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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