'Insurgent' Trailer: What Is Up With That Mystery Box?

Avid fans of the Divergent trilogy were overjoyed Friday with the release of the new Insurgent trailer, which was chock-full of action. However, that joy quickly turned to confusion for those familiar with the books on which the movies are based.

The beginning of the trailer shows a high-tech box with the factions' logos on it and Jeanine (Kate Winslet) is practically salivating over the mystery box. "What does Jeanine think is in that box Caleb?" asks Tris (Shailene Woodley).

Yes, Caleb, what does Jeanine think is in that box? Everybody is wondering because this mystery box was certainly not featured in the second Divergent book.

"I don't know, but she's testing Divergents, searching for the one that can open it," replies Caleb (Ansel Elgort). What!?

Read more Watch Tris and Jeanine Face Off in New 'Insurgent' Trailer

Things get even more confusing as the trailer shows people being tested with snake-like wires attached to them, wires that eventually find their way to Tris as she's tested in a room with the oh-so-special-but-totally-random mystery box.

There are already theories about what the box might contain, but they would majorly spoil the movie for anyone who hasn't read the books. Let's just say these four slightly spoilery words: serum, genes, experiment, Edith video.

Needless to say, there were some fans who disliked the idea that the movie might be, er, diverging from the books and they expressed their emotions on Twitter.

What's with this magical Divergents box in the new #Insurgent trailer? http://t.co/WqPSolfiEc

—Jessica Derschowitz (@jessicasara) December 12, 2014

I need to re-read #Insurgent because that trailer confused the hell out of me. Was there a mystery box in the book? Is my memory that bad?

—Fiona Pinkman (@fionapinkman) December 12, 2014

WTF? I just watched the #Insurgent trailer and I'm confused. A box? Divergents can open it? I don't remember reading that in the books

—Ronald B. Weasley (@GirlGryffindor) December 12, 2014

THE BOX THING MADE NO SENSE BUT OTHERWISE THE INSURGENT TRAILER LOOKS AMAZING

—sam (@anselxlouis) December 12, 2014

*cries at how theres a box in insurgent*

—cerys (@ceryshughess) December 12, 2014

NOT HAPPY WITH THE INSURGENT TRAILER THEY CHANGED SO MUCH... WHATS UP WITH THAT BOX THING??? ONCE AGAIN ANOTHER SERIES RUINED.

—mockingjay killed (@DauntlesKatniss) December 12, 2014