WARNING: The following contains spoilers for Watchmen Episode 8, "A God Walks Into Abar," which premiered Sunday on HBO.

At the end of Watchmen's seventh episode, "An Almost Religious Awe," Angela Abar takes a hammer to the forehead of her husband Cal, and removes a device, reawakening the omnipotent Doctor Manhattan, who had lay (mostly) dormant within him for the past decade. It's a shocking revelation that's explained in this week's episode, "A God Walks Into Abar," which takes viewers back to the beginning of their seemingly doomed romance.

But now that we know the drama's biggest secret to date (Sunday's finale will undoubtedly offer more), we realize HBO actually hid the twist in plain sight -- with a poster released a month before Watchmen's premiere.

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The striking image depicts Regina King's Angela Abar, dressed in her Sister Night costume, standing in front of a clock, a recurring motif in the comic book source material and on the television sequel. While most of us focused on the costume, it was assumed the blue glow in which she's bathed was a reference to Doctor Manhattan, who was bound to cast a long shadow on the TV series (despite the premiere establishing his presence on Mars).

However, in light of the revelation of "An Almost Religious Awe" and "A God Walks Into Abar," we now understand the true meaning of the poster: The glow of Manhattan isn't metaphorical. Angela is staring directly at the man she loves, Jon Osterman, aka Doctor Manhattan.

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The poster not only hints at Manhattan's presence on the show, it also teases the tight relationship between the two characters.

Watchmen's most recent episodes revealed the love story shared by Angela and Manhattan forms the very center of the series. It's the convergence point for all of Watchmen's byzantine plotlines, from Judd Crawford's murder to the identity of Will Reeves to the Seventh Kavalry's schemes. That poster was perhaps the biggest piece of the puzzle -- we just didn't realize it yet.

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 season finale airs Sunday at 9 p.m. ET/PT.

NEXT: Hooded Justice, Not Doctor Manhattan, Is The Superman Of HBO's Watchmen