How to Get Away with Murder creator Pete Nowalk set the bar high — and he knows it.

"I don't know if we'll ever top penis," Nowalk jokes to TVGuide.com, referring to Annalise's (Viola Davis) heavily hyped "final nine words" promo last year. "But there are a lot of OMG moments in the premiere." Indeed, the first Season 2 promo teased only one of them - which may not even be the biggest one.

"I was like, 'Oh, they only dealt with one story line. We have so many more,'" Nowalk says. "For a first trailer, that's good!'"

So what are these OMG moments? Where does Rebecca's killer rank among them? Nowalk gives us the scoop on what we can expect from Season 2.

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Who killed Rebecca? Unlike last season, which dragged out the identity of Sam's and Lila's killers, we'll learn who offed Rebecca (Katie Findlay) before the Season 2 premiere ends. Though he had no plan in mind when they killed off Rebecca in the finale, Nowalk decided over hiatus to reveal the culprit right away. "I just wanted to know and I wanted to move forward this new story," he says. "I guess it partly surprises me when people say it's gonna be the murder mystery for this season. For me, there's not enough there. People want to know and I like to turn the way we tell stories on their head. I think we found a way to reveal Rebecca's killer, which also starts a new mystery."

Nowalk hasn't heard any correct guesses yet — mostly because not many have shared them with him — but he hopes fans finds the reveal "real and intriguing." "What made me excited about revealing Rebecca's killer is we're learning something about that character in that moment," he says. "I feel really good about the way we figured it out."

Whodunnit... or not? The new case for the season won't necessarily be a murder. "I won't say if it is a murder or not. I don't really want to be tied down by the title. It's more about mysteries," Nowalk says. "[The case] culminates in another OMG moment. I think people should watch until the very last minute of the show because we like to end on a big moment and I think we definitely do. I think that's the one the promo is talking about."

Time to change it up In the same vein, the show won't completely stick with last year's past-catching-up-to-present format. "I'm not gonna say one way or the other what we're doing because that's part of the fun of watching it, but I love not telling our story linearly," Nowalk says. "I don't want it to feel exactly the same as last year, but we will continue to tell stories in a nontraditional way."

Annalise's blast from the past Not to oversell it, but Nowalk says this is a biggie. "We are gonna find out more about Annalise's past, which will be a really big surprise for people. I will go on the record and say I will be shocked if people don't say OMG," he says. "It's just an exciting character moment and insight into her." So is it a secret that comes to light or a person? "It's a reveal and someone from her past."

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The puppy is a pit bull The premiere picks up 10 days after the events of the finale and Wes (Alfred Enoch) is a changed man. "He's full of anger and we don't really know why. Obviously he's a suspect in [Rebecca's] death," Nowalk says. "He had really strong feelings about Rebecca, but he's not the puppy anymore. He's more of a pit bull in the premiere. I think Rebecca was a big lesson for him. He learned a lot from the relationship and I'll say that you will definitely see more of Rebecca."

Meanwhile, the relationship between the rest of the group remains strained and might get worse if Asher (Matt McGorry) works with the prosecutor on Nate's case. "He has a big problem," Nowalk says. "He had the DA who is putting Nate on trial for Sam's murder come to his door and clearly wanted to use him as some sort of spy, so he has a decision to make here. Does he spy on Annalise and betray Bonnie [Liza Weil] or does he go full fledge into Team Keating?"

To be Frank Will anyone else find out that Frank (Charlie Weber) killed Lila? Nowalk obviously won't say, but promises that we will learn exactly why he didn't hesitate to accept Sam's request. "We're gonna delve into the backstory of why Frank would do that for Sam. That very much involves Annalise," he says. "You're gonna see a lot more of Frank this season."

Nate's fate You're not the only one who pities Nate (Billy Brown). "Everyone feels bad for Nate. I feel bad for Nate," Nowalk says. "Obviously Annalise does as well since she made all this happen." Surely Annalise won't let him take the fall for Sam's murder — especially since she gave him that number for her secret lawyer. Might that person be Famke Janssen, who's recurring as a brilliant defense attorney?

"We'll see!" Nowalk teases, adding that the first few episodes will cover Nate's trial. "We have a lot of great guest stars: Famke Janssen, Amy Okuda, Kendrick Sampson and Matt Cohen. They're all part of mysteries, whether it's the same mystery or different ones, and it's connected to our main group. ... That's what excites me about this season: This whole season is about revealing stuff about the characters, finding out stuff about their past and who they are."

How to Get Away with Murder returns Thursday at 10/9c on ABC.

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