Arrow’s” Malcolm Merlyn (John Barrowman) isn’t a man who is known for his moral compass, but in the Oct. 21 episode of The CW drama, we’ll see the new Ra’s al Ghul faced with an ethical quandary when Laurel Lance (Katie Cassidy) and his daughter Thea (Willa Holland) arrive at Nanda Parbat with the body of Sara Lance (Caity Lotz) and a harebrained scheme to resurrect the long-dead vigilante. But as Thea’s own dip in the Lazarus Pit has proved, messing with the laws of nature always comes with a cost.

Below, Barrowman tells Variety about Malcolm’s new position as the leader of the League of Assassins, his relationship with Thea and what Oliver’s (Stephen Amell) mayoral bid means for Malcolm’s grand plans.

How has Malcolm taken to leadership of the League; is it all he dreamed of, or a case of be careful what you wish for?

Barrowman: It’s a combination of both, because our return to Nanda is through the eyes and the storyline of Thea and Laurel, and so we pick up however many months later… they come to him with a reason. We all assume that the League now is his, he is in control of that, and you’ll see in the episode how they are loyal to him. But the reason the girls have come back is to resurrect Sara, and Malcolm’s in a dilemma, because there his daughter is in front of him, and he was prepared to let her go and die because he knows the effect the Pit has on someone who’s brought back. So he’s reluctant to do it for Laurel, and there’s no love lost between him and Laurel, because she’s coming to ask for this favor and in the last season she turned to him during a big battle and said, in so many words, “thank you for saving my life, I wouldn’t do the same for you.” So it’s like, “girl, you’re coming into my house – what do you want me to do?” It’s very interesting, because you will see Malcolm being, in one way, ethical and moral with Laurel, and the audience is gonna go, “oh my God, Malcolm’s preaching here,” and then he has something that happens to his daughter in the episode, and he sees the change, and he does something that is totally the opposite of the morals and ethics he’s just preached to Laurel .So it’s the complexity of Malcolm and the reasoning behind why he does what he does – that’s what I love about him.

How concerned is he by Thea’s violent streak following her dip in the Lazarus Pit?

She is turning. [Laughs.] He’s not frightened, he’s not scared – very few things frighten Malcolm, as we know – he’s concerned. It’s his daughter, and as he’s made clear to everyone, if any harm comes to his daughter, he will lash out at them, he will get revenge. He’s very concerned that he takes care of her, and this is where that other moral dilemma comes in, because he does something, and the audience is gonna go “oh my God,” it’s gonna take them aback. It may shock some people, it may be like “well, I saw that coming,” whatever — it’s that flip of the morality that, for his daughter, he’ll do anything.

He spent a lot of time training Thea – would he ultimately like her to join the League as his heir, or does he want to keep her away from that life?

Even though she’s a young woman, I think he looks at her as a younger girl – he’s very proud of the fact that she’s come along leaps and bounds in the fighting aspect of it. We haven’t looked into that, whether he wants to see her as an heir, but what’s interesting about what’s to come is there will be a lot of obstacles in his way within his time in the League and as Ra’s — that’s all I’ll say.

Showrunners Marc Guggenheim and Wendy Mericle have said that they hope to explore a different side of Malcolm this season, in terms of who he is as a father to Thea – how have you seen him change in that respect so far?

That is starting, and he’s always been caring and always tried to get her to respond to his… not really affection, because you don’t really see much affection from them [but] … there are certain things that will happen that will make people go “oh my God, they’re father and daughter,” and then there are other things that will happen where they’ll be like “I totally understand and get why he’s doing it, it’s because [of] his love and his passion for his daughter” … It’s the future for him, really. The first part of it comes tonight in the episode, and that’s all I’ll say, because he does something that’s just off the wall for his daughter, really off the wall.

Wendy and Marc also said that even as his relationship with Thea is deepening, we’ll see a return to Season 1 Malcolm in terms of messing up Oliver’s plans and being more of a puppet-master behind the scenes. What’s he up to outside of his relationship with Thea?

Malcolm will be a great manipulator again, and I love the term “puppet-master” because that is exactly what he’ll be doing. As we all know with Damien Darhk [Neal McDonough] at the moment, chaos is falling on the city, and Marc and Wendy, I’ve always said to them when I go into the writers’ room and we sit and do read-throughs and stuff, in my head, Malcolm’s always watching. His eyes are in the dark shadows, letting this all happen and gathering all the information to figure out how to move forward, because when the time comes, he knows that that there’s going to come at some point a need for help, or he’s gonna have to step in. And that’s where the manipulation comes in, because you know that Oliver is thinking of running for Mayor, and that could be a great point for Malcolm to do some manipulating, that’s all I’m saying.

Is there any part of him that has considered trying to resurrect Tommy (Colin Donnell), or does he think the consequences would be too severe?

That’s something that’s never been written, but I know that Malcolm is greatly affected and hurt by what happened to Tommy. But as I’ve always said, Oliver is the son that Malcolm always wanted, and the fact that Oliver [was]  returning and coming to him for advice and help in previous episodes, Malcolm is thrilled by that. But when you watch tonight, you’ll see where Malcolm stands on the fact of this resurrection thing, because it’s not like it’s a spa where he’s like, “hey, come on in, let me resurrect you!” He wanted control of that for himself.

Nyssa (Katrina Law) obviously wasn’t on board with Malcolm replacing her father – what’s their dynamic like this season? Is she openly trying to undermine him, or biding her time?

Watch – that’s all I can say, because it’s awesome, what’s going to happen, because it’s unexpected. She bowed to Ra’s last season, she’s on her knees in front of him, but shall we say the pancake flips in the pan.

Damien Darhk was someone that the previous Ra’s saw as a huge threat; what’s Malcolm’s take on him and HIVE?

He’s a huge threat, but Malcolm is gathering information, and he’s figuring things out. He does realize how dangerous this man is, and how ruthless. Malcolm’s ruthless, but … Malcolm can’t figure him out, and that frightens Malcolm… When it’s something where Malcolm can’t walk in and deal with it, that scares him a little bit, because – and this is a word I don’t use very often with Malcom – it affects the people around him that he loves. Malcolm doesn’t show that love very much, but his way of doing it and fighting for them, he does love and care about certain people, and that’s what he fears the most, that his family that he’s finally got back is in danger.

This interview has been lightly edited and  condensed for clarity.

“Arrow” airs Wednesdays at 8 p.m. on The CW.