'Pretty Little Liars': Brendan Robinson Teases Lucas' Secret, Black Swan and Staying Bad

Pretty Little Liars Brendan Robinson Episodic - H 2012
Eric McCandless/ABC Family

Bad boy Lucas is in it for the long haul on Pretty Little Liars.

Actor Brendan Robinson said as much Wednesday morning following a dark turn made by his alter-ego on the ABC Family drama. As he tells The Hollywood Reporter, watching the Twitter feedback while the Chad Lowe-directed episode aired was a unique experience.

"It was the first time I had seen the episode and it was interesting," says Robinson, who next appears in episode 5 ("That was the first time I got to work with Lucy Hale"). "It was a mixed response because I think people were a little shocked. We saw a little bit of Lucas in the season premiere but not a lot, so I think people were shocked to see this very different side of the character which is nice which was the effect we were going for: shock factor."

PHOTOS: Summer TV Preview 2012

At one point during the episode, Lucas hints to former crush/friend Hanna (Ashley Benson) that Mona (Janel Parrish) may be faking her little "crazy" act, alluding to the clear idea that he knows far more than he's willing to let on -- to anyone.

"He definitely has a secret and he definitely has an 'in' to what's going on," he says. "Not that he's involved with what's going on but he definitely knows what's up." And Lucas' secret most likely won't be a rehash of his gambling and money problems introduced last season.

Robinson adds: "When I was filming this episode, I spoke to episode writer Joseph Dougherty about what exactly Lucas knows and he said it could go a couple directions at this point. It could be Lucas is in cohorts with Mona to trying to protect Hanna. it's open-ended at this point."

As he sees it, if Hanna opens her eyes a little more to what's actually going on in front of her, she may be privy to secrets bigger than her own.

STORY: 'Pretty Little Liars' Adds 'Revenge' Actor in Key Role

"Lucas' point of view is that everything is right in front of Hanna and all she needs to do is really open her eyes and really think about what's going on, and all the answers are in front of her," Robinson says. "It's a situation where he won't spill everything to her but at the same time, he's leading on the fact that she can figure it out herself. It's all right here."

Things with Caleb (Tyler Blackburn) also aren't great as the two former roommates are no longer living under the same roof. Even though there is trouble between Caleb and Lucas, in Rosewood everything can change at the drop of a hat.

"If you saw the teaser for next week's episode, there could be some stuff going down between Hanna and Caleb. Caleb may not have another option but to turn to Lucas," he says. "That would be interesting."

As for whether Lucas will revert back to his insecure, nerdy ways, Robinson says that his character will stay on this path for a prolonged period of time.

"I've been told that it's going to stay this way for a while," he says. "As Marlene King, our executive producer always says, everything in Rosewood happens for a reason. There's always a payoff. I don't necessarily know what that reason is."

The mystery of the Black Swan at the end of season two will be solved, to a degree.

"I do know the identity of the Black Swan," he says. "I didn't realize when we were shooting that it was supposed to be a mystery until afterwards when Twitter was ablaze. I know that will be addressed soon in the first cycle of episodes."

With a slew of new characters joining Pretty Little Liars, most recently Robbie Amell as Noel Kahn's older brother, Robinson says that at the moment he hasn't had any interaction with them but hopes that changes soon: "Hopefully in the future, that'll happen."

Watch a teaser for next week's episode:

Pretty Little Liars airs 8 p.m. Tuesdays on ABC Family.