WARNING: This article may contain spoilers for How to Get Away with Murder series finale. Read at your own risk.

How to Get Away with Murder series finale is coming this week on ABC, with the title "Stay." There have been a lot of questions that needed to be answered and mysteries to be solved in this final episode. The penultimate episode also raised another question as to who killed Hannah Keating.

How to Get Away with Murder series finale may explore who among the characters killed Hannah. Her death was ruled out to be suicide, but it seems like there's more to her case. Some people may want her dead, including those worried she'll testify for Annalise.

But perhaps, one of the biggest candidates is Frank. In the previous episode, Hannah was found dead in her home and ruled out as suicide. However, Bonnie suspected that Frank may have something to do with it since he found out that Hannah was his biological mother.

Frank might have actually done it out of anger and revenge. Speaking to Entertainment Weekly, Charlie Weber, who plays Frank, has something to say about this matter. He noted that "it's extremely likely," pointing out that his character might've killed Hannah and made it look like a suicide.

Weber explained he's the one who convinced series creator Peter Nowalk to let Frank be the one to kill Wallace Mahoney. This is an obvious answer and wanted people to guess it right every now and then. As for whether or not he killed Hannah, the actor said: "that is simply the logical answer."

Frank is a troubled ex-co and had to contend with his demons in the penultimate episode. There are a lot of revelations in his life and had to process all of it in just less than 24 hours. This might have led to him committing another murder.

Meanwhile, CarterMatt noted that either Bonnie or Tegan killed Hannah. But no matter who did it, everything may be altered given that Hannah was Annalise's potentially life-saving witness. Since this is the series' conclusion, there could be some unexpected turns of events here.

In the synopsis of How to Get Away with Murder series finale, Annalise found out that there's a surprise witness who could threaten her case. Connor attempts to persuade the K3 to go along with a new plan, while a lie between Bonnie and Frank threatens their relationship as the killer is finally revealed.

How to Get Away with Murder series finale airs on Thursday night, May 14, on ABC.