Joseph Gilgun, who plays Cassidy on AMC's Preacher, discusses Cassidy's struggles as a father, why he feels betrayed by Jesse and his favorite scenes to shoot this season.

Q: At what point in the season were you told that Cassidy was Denis's father? How, if at all, did that change the way you view Cassidy?

A: Sam Catlin had mentioned it when we shot the pilot. He said how funny it would be to imagine Cassidy having a string of unfathered children. I thought we’d touch on it and maybe meet one one day, but I didn’t think it’d be so soon. I knew we would calm and domesticate Cassidy ever so slightly and show a different side. An absent father is possibly the most shameful thing you can be. To not be around for your child is just appalling and if you haven’t got a really good excuse, you better get on the phone right now if you’re reading this! [Laughs] I think Cassidy is constantly letting people down and he’s ran away from all his problems. He knows what he’s done to this boy. It changed the way I played him in the sense that I know that Cassidy is inherently selfish. He’s not just a feeder, physically -- he’ll drain you of emotion. By not being with Denis, he’s drained the relationship of any real potential of it healing. I think he goes into that whole thing as a real asshole. He’s pretending like they’re best friends and he hasn’t been around for nearly 73 years. He’s a horrendous father that’s caused a lot of child trauma. We all blame our moms and dads for everything, right? Can you imagine being Denis?

Q: Do you think Cassidy was happy to come back to New Orleans in hopes of repairing this relationship? 

A: I think his intentions are to do good. He’s just having a go at it. This guy’s a f—king serial killer. It’s like, “How do I do this? I guess I’ll take him to the arcade. That’s what dads do.” He’s blindly taking a stab at being a dad, with no natural ability to father. There are really tender moments he does have, but he doesn’t know how to be a father figure and it’s too late. Denis is an old man and he’s lived his life by himself. He’s trying to catch up, but he’s doing it in unusual ways. He feels bad and wants to make it right.

Q: Why do you think Cassidy was initially so dead-set against turning Denis to save him? 

A: I think he’s thinking about the loneliness and feeling abandoned for 120 years. Everyone leaves you or dies and it’s just you. He’s hit the self-destruct button for a long time. The thing with becoming a vampire are the urges. It’s like being given an addiction to heroin with no experience of how to control your urges. Cassidy’s had 120 years of practice and has gotten to a stage where he doesn’t kill someone every night for the sake of it. He knows Denis will have a blood lust and doesn’t have experience harnessing those dark desires. It’s like, “Is this guy going to be a problem?” It’s about control and constantly battling the urge to do wrong. It changes the physical chemistry of your body and mindset. Denis is an ill, old man and Cassidy doesn’t know what he was capable of before he became terminally ill. His common sense is saying not to bite him. Denis has a very romantic image of what a vampire is, but it’s just not the reality.

Q: Cassidy eventually does turn Denis to save him. But in Episode 10, it seems his worst fears have come true. Do you think Cassidy regrets his choice?

A: Absolutely. The results speak for themselves. It’s just another mistake. When he does what he does for Denis, it’s all for him. It’s not for Denis. I don’t even think he’s being a father to Denis for Denis. It’s so he can take that off the list of terrible things he’s been a part of. I can only imagine having to watch that death, especially when someone is pleading with you to save their life. He bit Denis for himself. He wanted to make life easier on himself.

Q: How does Cassidy really feel when Jesse refused to use Genesis to help heal Denis? 

A: I think he feels completely abandoned. Ultimately, Jesse does the right thing. It is the right decision, but for Cassidy, who’s watched this guy use Genesis for whatever suits him, it’s a complete “f—k you.” "What a way to abandon your best friend and his dying son whose house you’re staying in, you bastard. You’ll play around with the police and make them hold hands. Is that what Genesis is for?" To add insult to injury, he uses it to put Tulip to sleep! He’s loyal to Jesse. He’s done nothing wrong. He’s done nothing but be a loyal friend to Jesse and when he says no, it’s a serious betrayal.

Q: Even though they're "best mates," why do you think the Cassidy-Jesse relationship is so volatile at times?

A: If you touch a nerve with Cassidy, it seems like he’ll do a full 360 and attack you – not necessarily physically but verbally. He’s very spiteful and he watches everybody. He’s cataloging these things. It seems that if the stars align in such a way where you put him on the front foot, he has no choice but to respond. He’s vicious like that. He’s a good, fun character, but he’s a piece of sh—t, really. There’s injustice in having his good intentions thrown back in his face, and Jesse reminds him of what he is, which is a drunk, lying, cheating drug addict vampire. Cassidy hates himself. He doesn’t like what he is. He doesn’t feel cool. Hearing that from the guy he loves and would give his life for is too much to bear.

Q: Given the battles with Saint of Killers (Cassidy lost his fingers!) and the Grail, does Cassidy ever feel that Jesse isn't worth all this hassle?

A: When you’re looking through the world through rose-tinted glasses, all the red flags appear as just flags. The glasses are coming off now. There are constant reminders now that this guy isn’t quite the fella he thought he was and this quest has gone to his head. All these things considered, Cassidy’s really starting to question not just whether he wants to be friends with this guy, but whether he likes Jesse at all. It’s comparable to one of those relationships where the husband is cruel but the wife feels like she needs him. He loves him; he’s just not in love with him. It’s an abusive relationship in a sense.

Q: You said last season you loved being covered in blood for the chainsaw fight. What has been your favorite stunt or gag this season?

A: I’ve got my own fangs this year, which is nice! I did a scene where my fingers have been cut off. That was good fun to shoot. I’ve not had many fights this year. I must request more next year. [Laughs]

Q: Last year, Cassidy had a run of digs against The Big Lebowski. This season, he’s a little more cautious when he mentions Terminator or Justin Bieber and clarifies his feelings quickly. Is he being more cautious with his pop culture takes?

A: [Laughs] I think he is. He’s slightly embarrassed. He doesn’t want Jesse getting the wrong end of the stick. It’s like, “I listen to Justin Bieber, but I’m still a tough guy.” I don’t agree with his Big Lebowski [take]. It drove me mad last year! I love that film. It’s one of my favorite films. I found it hilarious that Cassidy hated it.

Read a Q&A with Ronald Guttman, who plays Denis.

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