The season 1 finale of How To Get Away With Murder revealed that Sam Keating had ordered Frank to kill Lila Stangard, but fans were left puzzled when Rebecca Sutter was killed. Now, the mystery behind her death and the possible murderer is what seems to be the plot of the season 2.

The two-hour season 1 finale showed that Frank was a hit man for Annalise and that he was ordered by Sam Keating to kill Lila. Just before the episode could end, Rebecca is killed and her murderer's mystery is likely to be revealed in season 2.

ABC Network announced via a promo that it would return with season 2 of the pulsating series in next fall.

The promo said, "We promised you a killer twist and you got it. We'll be back with a whole new season of insanity."

How to Get Away with Murder season 2 will return this fall most possibly in September 2015 on ABC Network.

Meanwhile, lead star Viola Davis told The Hollywood Reporter that she is as clueless as the rest of the viewers about how the story will unfold.

According to the actress, Annalise does not know that Frank killed Lila, but she has an idea that Frank is capable of doing anything for the law professor because of his extreme loyalty.

Davis said, "I see him [Frank] as being very loyal because whenever you see an episode where Annalise gets in a bind, he's there saying, 'Is there anything you want me to do? What do you want me to do? How do you want me to handle this?'"

In the next season, it would not be surprising to see the writers playing on Frank's involvement with Sam that led him to kill Lila.

Meanwhile, Charlie Weber, who plays Frank in the TV series, spoke about the possible killer of Rebecca Sutter.

He told E!News, "It's entirely possible that either one of us, Frank or Annalise, killed her. We're so used to lying to each other and ourselves what it is we've done or are capable of. It's completely possible that Frank did it. But if you watch that last hour again, absolutely everyone had an opportunity to do it. So it's completely up in the air. It really could have been any of us. This was about self-preservation: she had dirt on every one of us."

Here are a few plots exploring what could be seen in the next season of How to Get Away With Murder

Who killed Rebecca?

Rebecca (Katie Findlay) was found dead at the end of the season 1 finale and the obvious suspect is Frank (Charlie Weber), who viewers learnt had murdered sorority girl Lila Stangard.

However, according to a poll conducted by Entertainment Weekly, Wes Gibbins could be the one who killed Rebecca.

Wes was super emotional at the end of the season 1 finale. And according to the website, Wes could have been convinced that Rebecca killed Lila and got infuriated and killed his girlfriend.

Also, since he was being played by his girlfriend the whole time, it makes sense that he could have lost his calm and could have just snapped.

Wes has already committed murder once, he killed Sam and it doesn't seem far-fetched that he would not kill again.

The Eggs 911 message

While Rebecca was under house arrest, she managed to send out an "Eggs 911" message to an unknown recipient. And given the fact that she died, this message could play a big role in the season 2 storyline.

The recipient of the "Eggs 911" text could possibly be the killer, as he/she feared that Rebecca could reveal some dark secrets.

Frank and Sam

Just because Sam is dead does not mean that he is gone for good. Now we have to figure out how this whole Sam and Frank relationship evolved, and what did Frank owe Sam that he had to kill Lila to pay for it.

Either way, we are in for some flashback in the new season.

Wes and Annalise are related

The last scene of the season 1 finale, where Annalise cradles Wes's head and tells him everything, is quite emotional for a tough lawyer like herself.

Also, since in the start of the season, Annalise has been a little easy on Wes and has given him the trophy, helped him in getting away with Sam's murder, and now has taken up Rebecca's case at his request.

It is no secret that she and Wes have this eerie bond, that other law students have pointed out throughout season 1, which suggests they're connected in ways that the show has not yet uncovered.

Connor and Oliver's relationship

Connor and Oliver's relationship started with casual sex, but quickly grew into one of the most talked about stories on the show. However, their was twist in the finale of season 1, where it was revealed that Oliver has tested positive for HIV, but Connor was negative.

Oliver then tells Connor that he should not be with him anymore and should find someone in better health. Will Connor stand by Oliver or move on, is another mystery that will unfold in season 2.