The first jaw-dropping twist of the premiere season has arrived, and it came just before the credits rolled on the inaugural episode of This is Us.

If you haven't watched NBC's newest drama, avert your eyes. The following article is pack to the margins with spoilers.

SPOILERS AHEAD

When the pilot began, viewers were introduced to five characters - Jack (Milo Ventimiglia) and Rebecca (Mandy Moore), a married couple expecting triplets; Randall (Sterling K. Brown), a man in search of his biological father after being abandoned as a newborn; and twins Kevin (Justin Harley) and Kate (Chrissy Metz). Although these adults seem to lead fairly disparate lives, they are all related thanks to a plot twist we never saw coming.

The grown up Kevin, Kate, and Randall are all Jack and Rebecca's children. After losing one of their triplets, the couple adopted Randall, raising the trio into the men and woman you see in the present. As you now know, that means the fateful birth of their children takes place in 1980, 36 years in the past. As the season progresses, you will see the characters in the 80s, the present, and everywhere in between.

"We kind of refer to it as 'a dramedy version of Lost'" series creator Dan Fogelman told TV Line. "You're going to get a real feeling of the evolution of a marriage...You might even meet [Jack and Rebecca] in the present day as older versions of themselves."

There were many ways Fogelman attempted to conceal the surprise, even if the outdated medical equipment tipped off some viewers. The trick? Cashing in on today's retro-hipster fashion trend.

"We have to tip our hat to the hipsters of the world. Because in their bedroom, they have a vinyl record player. And [Jack's] hair and his beard are exactly period, and his clothes and her clothes are exactly period," executive producer John Requa told Entertainment Weekly. "I live in Los Feliz; there are people dressed like that on the street every day. Hipsters really saved us."

Find out what's next when This is Us airs Tuesdays at 10 p.m. ET on NBC.

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