Which Question From The 'Insurgent' Livestream Got Shailene Woodley And Theo James All Flustered?

Trousers are involved. Don't ask us how.

Shailene Woodley and Theo James were live on YouTube today (March 5) to talk about the making of "Insurgent," taking questions from fans in real time.

The film's lead couple handled this off-the-cuff, rapid-fire interview like pros, but as with any live, unscripted broadcast, this one had a few surprises. Below, we round up the six most interesting things we learned about Shailene, Theo, and the making of "Insurgent."

1. Shailene and Theo have no trouble finding nice things to say about each other.

Each actor was asked to list their favorite thing about the other, and Theo didn't waste any time complimenting Shailene's generous spirit. And when it comes to what Shailene likes best about Theo, she says, "He's very intelligent."

2. In real life, Shailene would prefer to be (gasp!) factionless.

"I wouldn't want to be dominated by any particular force," the actress explained, when asked which of the five "Divergent" factions she would choose for herself.

Not so with Theo; both he and Shailene agree that he'd be right at home in Amity, farming things, forever.

3. Theo actually hasn't read "The Fault in Our Stars."

Turns out, the actor wasn't toting the book to the gym in order to read it on the elliptical; he was just bringing the volume to Shailene, so that she could sign it, as a favor to some fans.

4. Theo's on-set nickname makes absolutely no sense.

For reasons unclear, Shailene sometimes refers to her co-star as "T-Dog." Why? Nobody will say, which means we might as well make a bunch of ridiculous guesses. (We'll start: It's an homage to the greatest "Walking Dead" character to give up his life when zombies invaded the prison.)

5. Both actors would love to make an "Avengers" appearance -- but not for the reasons you might think.

The one actor that Shailene and Theo are both dying to work with? Mark Ruffalo.

6. And finally, something shady happened on set, and it definitely involved a pair of pants.

The biggest mystery (and most awkward moment) to emerge from the livestream happened when someone asked the actors about embarrassing moments while making "Insurgent," and Theo muttered something about "trousers," and then both of them started giggling. What? Yeah, we have no idea, and both stars pointedly refused to elaborate further. We'll just have to imagine what that story might be.

Best guess: It starts out with something like this.

via professionalfangirls.com

"Insurgent" hits theaters March 20.