'How To Get Away With Murder' Season 5 Theories: Who Killed Nate Sr? Does Evidence Point to Emmett?

How to Get Away with Murder returns Thursday night on ABC for the second-to-last episode of the series' fifth season. While last week brought quite the plot twist, fans are still reeling and have one question: Who killed Nate Sr.?

As a refresher, last week's episodes big plot twist came when a withheld number called Annalise. The person behind the phone was revealed to be Gov. Birkhead, and she contacted the powerhouse lawyer to present damning information. Not only did she claim that she had nothing to do with Nate Sr.'s death, but Gov. Birkhead also revealed she knew who did it.

"You know him, too," Birkhead told Annalise.

She presented Annalise with a file and said Emmett Crawford was the perpetrator.

Watch the full ending to episode 13 below:

In a sneak peek clip of Thursday night's episode, Annalise delivers the evidence to Nate. While it's unclear of what the envelope contains, but it looks like Annalise believes everything that is presented by Gov. Birkhead.

"I didn't want to tell you until I knew it was true," Annalise tells Nate in the episode's clip. "Emmett called Paula Gladden the night your father was killed, and they were talking weeks before like they were planning it."

The evidence does look convincing in the case against Emmett; however, fans quickly questioned the reliability of the evidence's source, Gov. Birkhead, who was being framed for the murder months earlier.

Here are the most popular theories of Nate Sr.'s murderer, compiled by Romper.

Gov. Birkhead

One Reddit user said Birkhead had "a lot to gain" from Nate Sr.'s death, especially since she is a suspect in Miller's murder as well.

"She had a lot to gain from Nate Sr's death, and now that the FBI has her as a prime suspect in Miller's death, she has a lot to gain by pushing suspicions onto Emmett," Reddit user allij0ne wrote. "If she can make people believe Emmett and Miller worked together on Nate Sr, she probably assumes people will suspect him too."

Annalise does mention a suspicion that Birkhead is simply "framing the only person she could think of," however, Nate does suggest that the governor may be telling the truth.

Jorge Castillo

Though Laurel's father has been in jail since Season 4, some fans are convinced he could've sent a hit out on Nate Sr., making Emmett a possible red herring. Proposed by Reddit user, htgawmfrea, Jorge being the possible hitman could explain why writers have been making some viewers dislike Laurel since Season 3.

"[Laurel's] daddy is still involved and likely responsible for the hit on Nate's father, Emmit is a red herring. Even if [the writers] reveal [Emmett] did do it, they never reveal anything earlier then a finale; unless it has a twist or introduces a new storyline. Even if [Emmett] was the shooter, Jorge ordered the hit."

"the writers have been doing a great job since season 3 making us slowly not like her and I think it's for a reason. they've been alluding to more with her history and character for a reason," the user added.

Nate Sr.'s Murderer Is Someone We'd Least Expect

While it's possible that Birkhead, Emmett and/or Jorge are the most likely of suspects, it is also possible that writers will throw a curveball. One Reddit user said, though "a stretch," Bonnie could possibly be the person who put the hit on Nate Sr.

"Her whole reaction after finding Nate in the bushes just looked suspicious to me," user hiphopshelter wrote in October. "I'm probably reaching but the way they supposedly revealed that Miller put the hit on his father just felt strange thus making me believe that there is actually a lot more to that story."

Other fans offered "longshot" guesses of either Gabriel or Nate Sr. taking his own life with an officer's gun. With two episodes left to go in the season, hopefully theories can be put to rest and the audience can finally get answers.

Find out what happens next when How To Get Away With Murder airs on ABC at 10 p.m. ET.