If you're fully caught up with the thrills of "The Following," then you already know that Shawn Ashmore, who plays FBI agent Mike Weston, has had some hard-to-stomach scenes this season -- with none more brutal than the climactic moment in the most recent episode, when a text message from antagonist Lily ended up containing a video of Mike's father being murdered.

Watching Mike watch that video was agony for the "Following" audience. But for Ashmore, it was a different sort of challenge entirely. Because -- and hold on to something, because we are about to blow your mind -- when we watch Mike watching the video, the actor playing him wasn't watching anything at all.

"The crazy thing about that final scene, where I see my dad die, is that they hadn't actually shot the video of my dad being killed," Shawn revealed to MTV News in a recent interview. "I didn't know what my dad looked like, I didn't know the actor they were going to get to play him. It was a really tough scene, a really emotional scene, and I'm really happy with how it turned out."

In other words, the actor had to create that horrified, tearful reaction out of whole cloth, and play it to a blank, green screen: no small feat when it came to filming one of the most wrenching moments ever on a show where hard punches to the feelings are de rigueur. For Ashmore, though, having to play with incomplete information is just part and parcel of making one of the most suspenseful shows on television, where not even the cast is aware of where they're headed from week to week.

"To be honest, as an actor on the show, the endgame is always in question, because we always get the scripts at the last minute. We start shooting the last episode this Monday, and I haven't read the script yet," he said.

Pressed for hints about whether there was something -- anything! -- he could tell us about where season two might end, Shawn alluded to upcoming plot developments that Mike Weston will be "right in the middle of," saying, "I can tease that there's a giant spoiler, a huge twist coming up, that I don't think anyone is going to see [coming]. I can't wait to see how the audience is going to react to it."

But when it comes to the final moments of the show's second season? He swears that "as far as the real endgame, I'm in the dark as much as anybody else."

And when it comes to the possibility of a happy ending for the good guys of "The Following" -- whoever they turn out to be -- Shawn can only speculate that it doesn't exactly look good for them, does it?

"These guys have been put through the meat grinder, emotionally," he said. "They've had to take lives, they've lost people who were very close to them, they've had their own lives almost taken. I think that affects a person. I look at these guys as sort of soldiers at this point, they're part of a war. I think there may be some satisfaction at the end, maybe a little closure, but I don't know that these guys will ever go back to being happy. I think that's a tough journey for them."

Meanwhile, with the show just renewed for a third season, that journey is set to continue for a while yet -- with who-knows-how-many emotionally torturous moments yet to come. But Ashmore says that he's thrilled to be along for the ride, not just as a castmember, but as a fan.

"To get to play something where you get to be so vulnerable, so open, so raw -- I mean, that's kind of what you're looking for, to find those heights as an actor," he said.

And despite being on the show himself, he's not immune to the allure of this thoroughly creepy and disturbing concept of a serial killers' cult.

"At the end of the day, we do spend a lot of time in that sort of dark zone, but I love the storytelling. I love a great thriller. I love the horror genre. And I know what this kind of storytelling does for an audience," he said. In fact, Shawn -- who admits to gleefully watching people's shocked reactions on Twitter when the show airs on Monday nights -- has his own particular wish for the audience of "The Following" every time an episode concludes:

"Hopefully they lock their doors and they have a nightmare that night."