Spoiler alert: Do not read until you’ve watched the season finale of Fox’s “Scream Queens.”

It’s been quite a bloody season at “Scream Queens'” Wallace University, which has been terrorized by a serial killer — make that a trio of killers. First, we learned that Boone (Nick Jonas) was one of the culprits in the Red Devil suit; then we learned that Gigi (Nasim Pedrad) was not only his accomplice, but the woman who looked after him when he was a baby, also known as the baby-raising “hag.”

Our intrepid on-campus sleuths — Grace (Skyler Samuels) and Pete (Diego Boneta) — even figured out that the third stalker was Boone’s sister — the other baby born in the bathtub in the series premiere. Of course, Pete wasn’t exactly innocent: Once he discovered Boone’s involvement, he got caught up in his mission — and paid the ultimate price himself.

So it was just a matter of unmasking the final guilty party.

In the season finale of executive producer Ryan Murphy‘s comedy/horror series, we finally learned her identity: Hester (Lea Michele), aka Chanel #6, the neckbrace-wearing, death-obsessed Kappa Kappa Tau pledge. And thanks to her ingenious, albeit wacky plan, she even managed to get away with it.

Turns out the unhappy family members — Gigi, Boone and Hester — had spent 20 years in an insane asylum painstakingly plotting their revenge on the sorority. “I was the brains of the operation,” explains Hester, who even faked scoliosis as her “cloak of invisibility.” She stabbed herself in the eye with a stiletto, framed the other Chanels (who ended up in that same asylum after botching their defense at trial) — and ended up the treasurer of the newly reformed Kappa Kappa Tau.

Here, Michele talks to Variety about playing the killer — and what it means for a potential Season 2. “I’m really feeling like a job well done for 2015,” says Michele. “I wrapped up ‘Glee.’ I’m happy to have another season of a successful TV show under my belt. I’m giving myself a pat on the back.”

When did you find out you were the killer?

I found out in New York at a press event for the show. It was right when the script for the finale had gotten released. Keke (Palmer) told me. I hadn’t even read it yet. I was like, “Who’s the killer?” She said, “It’s you.” So nonchalant! The first thing I wanted to know was, “Do I die?” And she said, “No, you get away with it.” I had to corner Ryan and get all the information. I was like, “Listen. I’m beyond happy to be the killer, but I want to make sure I don’t die. And that I come back next season.” And he was like, “You’re fine.”

Did you suspect you were the killer? When we talked at the beginning of the season, you weren’t sure.

I really didn’t. Being on the show was good enough. I didn’t think they had it in mind for me to be the killer. I thought that Oliver (Hudson) was the killer, or Skyler (Samuels). Because they were these two incredibly wholesome characters so I’m always looking for what’s not right. But maybe that was too obvious.

How did the cast react to you being the killer?

Some people did think it was me. Emma (Roberts) thought it was me for a long time. A few people thought it was Skyler. It was 50/50.

What direction did you get on how to play it?

Brad Falchuck directed the final episode. And I think that it was so great getting to play her whole backstory. Up until the finale, I had played Hester like she was obsessed with the Chanels. And then to get to really see how her brain has been working and how she’d been raised was so fun for me to play.

How do you think fans will respond?

I hope that they like it. I hope they love Hester. And when you do find out that she didn’t actually kill anyone — she only killed Pete, but he was murdering people — she sort of makes that her way out of getting out of this with her hands clean. It makes you sympathize with her even more so that you’re not loving a killer. You’re just loving someone who had a really crazy plan.

It’s surprising that she gets away with it.

It’ll bring such a great texture to next season, if we get lucky enough to get to come back. It’ll be great to get to play her keeping this secret and being a victim of what will be a new killer for a new year.

What can you reveal about next season?

I do know what Ryan’s plan is and it’s really fun. It’s an homage to another classic horror film. This year was “Heathers.” Next season would be a take on another classic girl film. I’ve had a great time playing Hester, and hopefully she’ll be back to play next year.

So you’ll be playing the same character again?

Yes, we’re playing the same characters in a new location. We would all go somewhere, and it’s explained why we’re going where we’re going. Hopefully Emma Roberts will be back for sure, too. (As for everyone else), it depends on how many gift baskets to Ryan Murphy Productions people can send in time. I think the cast is so incredible. I know Ryan is loyal to everyone, so hopefully everyone will be able to come back at least for something.

As you look back over the season, what moments stand out to you?

I loved getting to do everything with Emma. Getting to do scenes with her is like playing tennis with Serena Williams. As an actor, she forced me to stay on my toes and keep up with my game. That girl is never off. She is always on. And I loved working with Glen Powell. He is so funny. Working with him, I felt like I was on “SNL,” the most fun acting class that I could ever do. I’ve known him for so many years, so now to be on a show where we get to play such wacky characters together was really fun.

You also had a great scene with Jamie Lee Curtis, where she confronts you about being the killer.

How do you prepare for that? Those moments are so surreal you can’t even grasp them. It’s not until months later that you stop and go, I did an amazing scene with Jamie Lee Curtis. She’s such an icon. What I love the most about meeting people like her is they surpass what you ever thought. You love them in films and you know great things about them, and then you meet them and they’re even more incredible than you could have ever imagined. And kind and sweet and strong and loyal. Doing that scene was just incredible. I made sure my mom was on set that day so she could watch it all go down because my mom loves her so much.

The finale was pretty gory, but also laugh-out-loud funny. How do you balance humor with horror?

That’s the greatest thing about Ryan’s writing. Ryan, Brad and Ian did an incredible job of enlisting such a great group of actors and actresses who really understand how to handle that balance of comedy and yet that intensity. Definitely for me, as an actor, it was the most fun thing to do, to get to be sneaky and dark and also funny. That scene with Jamie Lee where we are having that nose-to-nose intense conversation, and then we’re like “OK, cool, bye,” I thought was so hilarious and awesome. If it goes to another season, (her character, Dean Munsch) knows that it was me. That’s awesome.

It’s mutually assured destruction.

We’re in it together now, she and I. I know a lot about her. She knows a lot about me. That will be a lot of fun to play with.

The finale also delivered a message against the Greek system and hazing: 104 deaths since 1970.

I never went to college. I’m incredibly uneducated on that whole world. I wouldn’t survive a day in a sorority. But I know that there’s definitely some intense things that happen. I think what Ryan always does is he takes these important issues and he injects them with humor and gets the point across. Obviously we did that a lot on “Glee.” And this was done in a much more theatrical way. But it’s really smart. It gets you thinking and talking about things in a more lighthearted way.

Are you going to miss that neckbrace?

Nope! I was so happy that, in that final scene, she wasn’t wearing it. I hope that it means it’s gone for good.