How Eugene Simon Became Game of Thrones' Scary New Bully 

Spice up your Memorial Day BBQ with a spiral-cut hot dog!

Has Your Show Been Canceled? Check Here!

The High Sparrow has found his scariest disciple in Lancel (Eugene Simon), formerly of House Lannister.

(Sundays, 9/8c, HBO), the Lannister cousin has abandoned his rich, corrupt family to join the Faith Militant to exact justice on behalf of the Faith of the Seven in King\'s Landing. During the last episode, Lancel flexed his holy might to confront the worst sinner of them all: brothel owner and schemer Petyr "Littlefinger" Baelish (Aidan Gillen). Somehow, Littlefinger managed to escape from the encounter unscathed.

"I remember thinking: What is the reason that Littlefinger is not immediately grabbed, arrested and thrown in jail? He is, as Lancel says, a flesh peddler," Simon tells TVGuide.com. "I very much read it as Lancel is sort of playing with his food at first. Part of him is aware of the way he can intimidate people. [Littlefinger] is a perfect rib-eye steak of meat that needs to be cleansed of his sins, that Lancel wants to burn in hell, but doesn\'t want to arrest quite yet."

"That, you could argue, is definitely the darker side to Lancel that has appeared," the actor continues. "Punishment and penance are at the heart of their ideology."

Lancel has made quite the transformation when he returned to King\'s Landing this year after a two-season absence. Gone is the silky-haired fop whom Cersei (Lena Headey) made her pawn and Tyrion (Peter Dinklage) blackmailed. Enter the shaved-headed fanatic who\'s been the High Sparrow\'s muscle in apprehending those that the Faith deem morally corrupt, including the former High Septon and Ser Loras (Finn Jones).

The character\'s evolution is one reason why Simon has always been glad to have lost out on the role of Joffrey, for which he initially auditioned. "Jack [Gleeson] was just a far better Joffrey than I could\'ve been, but also, I genuinely do love the role of Lancel a great deal," Simon says. "Whenever he comes on screen, he\'s usually gone ahead and changed something. He\'s gone ahead and burst into a brothel and sacked the entire place. Or he\'s slept with the queen. Or he\'s been dying on a deathbed. Or he\'s been converted to an extremist religious group. It keeps me very much on my toes."

We saw Lancel confront Cersei about their past sins together. Did Lancel actually think he could get her to repent?Eugene Simon: She is at the very center of his motivation to continue with his work. He has such personal insight into her life. He sees her as the absolute Mount Everest of goals to convert. If he can convert Cersei, he can convert anyone. ... The guilt he used to feel and the penance that he himself must pay in order to be viewed in favor of the gods is dependent on her too.

Was it a surprise to you to come back and find out Lancel was this physically strong character with short hair? In the books, his battle injury made him frail and age prematurely.

Simon: It was! The visual aspect of Lancel was so exciting when they told me what they wanted him to look like. It\'s such a frighteningly powerful statement and change. Not having a wig was quite a relief. I just got [this short haircut] for the show. Usually I have lots of hair, but when I cut it, I realized I had a scar from banging my head open when I was a kid. When we cut it and saw it, we thought, "My God, that really suits the character."

How different is it to wear plain robes compared to that courtly garb from before?

Simon: It makes getting into costume so bloody easy. No knee-length boots, no leather, no sword, no wigs, no nothing. I am a blessing to the costume-makeup department.

What was it like to return to such a different character after two seasons of being away?

Simon: It was sort of like coming back to a new job really. It\'s a Goliath of a show now, so in that sense, the pressure was on to make sure that I was up to scratch with my acting. In terms of my attitude of coming back to Lancel, I had actually been preparing for a long time for this change -- the change that you and I know from the books, but it\'s different in the series. I was quite raring to go, for people to see just how this boy figure in the first two seasons could become someone of such influence and intimidation through really being at first an underdog.

Why has Lancel had such a change of heart? What does the Faith give him?

Simon: The wound that he received on is shoulder from the Battle of Blackwater is a good metaphor, if you like, for what he went through emotionally. That wound nearly killed him. For Lancel, he believed he was on his deathbed whilst he was missing for the past two seasons, and that made him emotionally distraught. He realized he had just been used this whole time. No one in his family was there for him, even the one he naively loved the most, Cersei. And then enters this very interesting figure in the form of the High Sparrow, [played by] Jonathan Pryce. The High Sparrow has this wonderful talent for empathizing with people\'s pain and uniting them, rather like the King Beyond the Wall in some ways. That is what he was able to do with Lancel, to show him a path of redemption and forgiveness, but only through penance. Lancel\'s become a figure of righteous retribution.

Lancel showed just how devout he was by getting that emblem carved on his head, which was an extreme scene to watch.

Simon: I\'ve healed since then. I have Wolverine-like healing powers. [Laughs] It\'s a symbol of commitment to the Faith Militant, the militant wing of the Faith of the Seven, but really represents the more aggressive and, dare I say, expansionist attitude to want to maintain the Faith as the majority religion of Westeros. But I don\'t think it\'s just a religious movement. The politics behind this religious movement is to do with trying to help many of the impoverished and destitute in King\'s Landing out of poverty.

What is Lancel\'s biggest strength and biggest weakness?

Simon: I think that his biggest strength is probably his inability to emotionally empathize anymore. It makes him more or less unstoppable. He is totally resolved. He would die for his conviction and belief in the Faith. And that makes him rather weak in some ways because he\'s lost it, he\'s lost his humanity

Does the Faith Militant have any sort of formal military or fight training?

Simon: I think at the moment they\'re at a very adolescent phase. They use clubs and large knives, machetes, basic peasant-style weaponry. I spoke to George R.R. Martin quite recently. In the past, he said they used to be armored.

Simon: The Mother, Father, Maiden, Smith, Crone, Warrior and Stranger are the seven deities of the One God. There are the Old Gods, and there are the New Gods. You might say they\'re like Protestants and Catholics; one is newer than the other. They originate from the same major events ... You will get a better understanding definitely of the origins of the Faith as the series goes on.

Simon: I think anyone that sits on the Iron Throne is automatically becomes a ticking time bomb for Westeros. But I would like to see Arya on the throne. I think she\'s got a perfectly good balance between revenge and justice.

If you were like Hodor and could only say one word your entire life, what would that word be?

Simon: This is probably the most important question of the entire interview. It would be "help." [Laughs] Because no matter what happens, that would be a word I would need at some point in the future. If I want to say yes, I\'ll just say "Help..." If I want to want say no, I\'ll go (in a lower voice) "Help." I\'ll scream "Help!" if I need it. And I\'ll go, "Help?" if I don\'t know what they\'ll need. So it\'ll be perfect.

airs Sunday at 9/8c on HBO. Get a preview of Sunday\'s episode below:

Tags: Spring Preview 2015, Interview, Spring TV, HBO

Here Is the Game of Thrones-Coldplay Musical You Never Knew You NeededEmilia Clarke as a Rastafarian Khaleesi and more!

Mega Buzz: Are Margaery and Loras Doomed on Game of Thrones?The High Sparrow may know more than he\'s letting on!

Peter Dinklage Sings About Everyone Who Died on Game of ThronesIn a song written by Coldplay!

Game of Thrones: Why Sansa\'s Rape Won\'t Define HerPlus: Our thoughts on Loras\' birthmark

U.S. Senator: I\'m Boycotting "Disgusting" Game of ThronesThe backlash over Sansa\'s wedding night continues

What Is with Game of Thrones and Its Horrible Weddings?Love has no place in marriage!

1. Grey's Anatomy: Arizona & Alex: The First Flight

2. Mistresses: Toni Seduces Dom While Savi's Away

3. Desperate Housewives: Actors Picking up Character Traits

© 2015 CBS Interactive Inc. All rights reserved.

Photo Credits: Helen Sloan/HBO; Macall B. Polay/HBO; NBC; Corbis