As it turns out, the stars of 'Pretty Little Liars' really can keep a secret.

TV Squad caught up with Troian Bellisario, Ashley Benson, and Shay Mitchell at ABC Family's upfront event last week, and all three ladies were frustratingly silent on what fans can expect during next week's season finale.

"All of the girls have dealt with so much the entire season, but nothing will compare to what they have to deal with in the season finale," said Mitchell, who plays Emily. "And I am talking slow because I totally could tell you everything. But that would ruin it, and I'm not going to. So I have to be very careful in what I say. But it's going to end with a bang."

Fortunately, after a little bit of coaxing the ladies finally dropped a few hints about what will take place during 'For Whom The Bell Tolls.' Benson, who stars as Hanna, specifically said the last five minutes are a must see. "All four girls are put at high risks. We're pushed to our limits. We go through this huge obstacle course," she said. "I really can't tell you too much, but the last five minutes are unreal. You get very close to knowing who 'A' is. Insane things happen!"

Bellisario agreed, saying just like the mid-season finale, things will end on a big cliffhanger. "We are not going to disappoint," she said. "I think they've only upped the ante for this one."

Filming on season two doesn't begin until next month, but Mitchell said the finale should explain a lot about what's to come. "Obviously, it's going to be something a little different. After seeing the season finale, you're going to know what I'm talking about," she said. "But things are going to have to change. So I think each of the girls' lives are going to drastically change from just what goes on in the season finale."

As for her character, Spencer, Bellisario said she expects to get some answers about what happened to her the night of Alison's (Sasha Pieterse) disappearance. "I think you're going to find out what happened soon," Bellisario said. "And the real scary thing is, what are the ramifications of that?"

Fans won't have to wait too long to see those changes unfold -- the second-to-last episode of the season airs tonight on ABC Family, with the finale scheduled for March 21. 'PLL' is slated to return for its second season June 14.